The first step is to remove the cluster and have a look.  You can’t order the gears until you check what you have, as the various combinations of instrument cluster use gears with different numbers of teeth.   The factory tool to remove the cluster is not necessary.   The easiest way to get the cluster out is to remove the speaker and push it out from behind.

Once removed, the instrument cluster can be unplugged (there are a lot of plugs) and brought to a workbench.  The first thing that must be removed is the exterior temperature display.   It is held onto the bottom of the instrument cluster with two screws and simply slides out.   These two screws also hold in the speedometer.

Next, there are four more screws to remove the speedometer housing.    They are the gold ones with the hexagonal heads on the edges.

Once those screws are removed, the entire assembly for the speedometer just lifts out, once the warning light that clips on is removed.    At the same time, the two smaller inner bulbs for the indicators, and larger outer bulbs for the illumination should be removed.

It is not possible to repair the odometer while the speedometer is still in its plastic housing.   The four inner screws must also be removed.   On my cluster they were the silver phillips head screws, but I’ve also seen gold flathead screws on other clusters.

The speedometer unit lifts out, and care should be taken to not lose the four rubber spacers that go on the plastic feet that stick through the circuit board.   There are also plastic baffles for the light bulbs that slide out.

With the cluster removed, you can see the original vivid orange the speedometer needle was, as well as the the max speed markings and 50/60 hatching.  These should all match, so I elected not to repaint my speedometer needles, as I do not have a steady enough hand to repaint the sections on the speedometer face.   They look terrible when they don’t match, as well as looking terrible when painted red, not the factory orange.

The odometer gears are accessed to the right of the speedo.   There is a cover held on by two tiny philips head screws.   In the picture above, the cover has already been removed (top right) and the tiny screws are on the table.  The cover is a bit of a pain to get off, due to the black box.

With the cover off, it is easy to see the three gears that wear.   The small one, from the drive motor on the right, the top one, and the next one.  There are also two more gears that don’t seem to wear and do not need to be replaced.

The main thing to do here is to remove the two larger gears and count the teeth on the inner gear for each.  The outer teeth seem to always be 48, but the inner teeth vary.   I guess I’m going to need reading glasses soon, as I couldn’t count the inner teeth without the magnifying glass app on my phone.   When I last did this a few years ago, I didn’t need any assistance!

The picture below shows one of my gears, including the missing teeth.

The smaller gear always seems to have 12 teeth, so does not need to be counted.   There also seems to always be a 12/48 gear.   However, for my 560SEL with a 260KM/h speedometer and a 2.47 rear end, I needed a 14/48 gear.   My old 300SE needed a 13/48 and my 560SEC with an MPH speedometer needed an 18/48.   I purchased my gears from Garagistic.

By the time the gears arrived, plus I had a bit of work travel, it had been a few months since I removed the cluster.   It is a pretty simple matter to remove the two larger gears, but the original small gear is on a brass bushing, which is no longer needed.  The easiest way to remove it is to break it with a set of cutting pliers.

Once that is off, the new small gear is just press fit on.  The two larger gears are much easier to put in.   At this point, I made a mistake.  I assumed that the white gear was the replacement for the light coloured gear, and the blue gear was a replacement for the black one.   I put everything together and tested in the car.   It didn’t work properly.   I then removed it all again, and looking at the photos of when I did my 300SE, I realized I had them backwards, and it was binding.   The blue one should have been the top one.

I also used a small amount of rubber grease, as I found I could hear the gears on my 300SE with no lubrication.   As can be seen from one of the pictures up above, the original gears were lightly lubricated.

At this point, I also thought I would try replacing my broken clock with a different one.  I have a few spare W126 instrument clusters, so I removed the clock/tacho from the one that was in the best visual condition and swapped it over.

This was a pretty simple thing to do, but proved futile, as the replacement clock didn’t work either.   I put my old one back, as it was in much better visual condition than the other two spares.   Removing and the bulbs for the illumination a couple of times caused them to fail, so I ended up replacing both of them.  I keep bulbs like this on hand so it was easy to do.

In doing this testing, I didn’t push the cluster back in properly which made it easy to take it in and out until I was happy with everything. Once I was, I pushed the cluster back in place and replaced the speaker.

The final test was to check the accuracy of the odometer with my GPS.  On a 2.8km course, the trip odometer recorded 2.8km, so I was happy with the result.    I’m glad my 560SEL odometer repair is finally done, as I don’t like to drive cars without a working odometer.

The post 560SEL Odometer repair appeared first on Classic Jalopy.

At that point I was preparing the 560SEC for the concours run and the 300TE for the Tasmania trip, so I parked the 560SEL to look at after those events.

I assumed that the problem was going to be a broken plastic slide in the window regulator.  This is a very common problem on the W126.   I was so sure this was the issue that I bought a couple of these slides online.

Earlier this year, I finally removed the door trim and the slide was in perfect condition.  Removal of the W126 door trim is wel documented, but there are a few gotchas.   The first is that the trim should never be pulled outward until it is pulled up and plastic hooks are clear of the door.   They will break otherwise.   Secondly, there is a tiny plastic circlip in the electric seat switch.  This is often missing, but was still present on my car.   All the other doors I’ve removed the trim that had power seats were missing that circlip.

I couldn’t see any obvious issue other than the window being stuck.    At this point I was preparing for a couple of work trips, so I took the car to a mechanic to take a look at it.   He removed the regulator and diagnosed a bad window motor.   He showed me how the plastic gear inside the motor was binding up preventing the motor from working.

Enter the 420SEL parts car.   I removed the motor from the front drivers side.   The other motors are different and have different part numbers.    The parts car motor looked a bit manky but it did work.   I cleaned it up as best I could and dropped it off.

The parts car motor did the trick and I got the car back with a working window.    My job was to put the trim back on.   The first part was replacing the moisture barrier.   The original one had a few rips in it, so my daughters and I made a new one from some plastic sheet, using the old one as a template.

As well as the moisture barrier, I also replaced the pot metal bracket that goes around the door pull, and exchanged the door pull with one with slightly less play in the mechanism.  The door pulls from the rear doors are the same and are generally less floppy.  The metal bracket was broken as can be seen.

The main trick with getting the door trim on is to remove the little trim strip that goes alongside the window aperture.  It is held in with a single screw and then it lifts upwards and away.   This allows the top of the door trim to better fit into the channel near the window.

The puddle light is also a bit of a pain as once its connected you need to keep the door trim near the door.     From there the job is fiddly but not all that hard.   The main thing is not breaking any of the clips when re-attaching the trim.

It’s been good to have the 560SEL back and operational.  I’ve been driving it pretty much daily for the last week.

The post W126 stuck power window appeared first on Classic Jalopy.

Values aside, how does the experience actually differ?   We have a short wheelbase six cylinder example of each.   A 1979 280SE and a 1986 300SE.   Both cars occupied the same place in the Mercedes-Benz line up, with the first generation W126 280SE coming in between.

Our W116 is a 1979 model, the last full year of production.   It is a highly optioned car, as run out models typically were.    Being a late car, it has the more desirable velour carpets and dash wood.   As an Australian delivered example, it suffers from the ADR27A pollution controls, which hampers performance a fair bit as compared to the standard model.    On the plus side, it has self-leveling rear suspension, which offers a great ride.

The W126 is a 1986 model – the first full year of production of the second generation W126.   In Australia, at least in 1986 and 1987, many features that would be standard were still optional.   The car has MB-Tex seats, no sunroof and was originally sold with plastic hubcaps.   Being an Australian deliverd car, it has self-leveling suspension, burl walnut trim, rear reading lights etc that were not commonly found on the standard 300SE.

Styling

While the W126 is a facelift of the W116, their styling looks quite different at first glance.    The W126 is a bit of a mix between modern and classic, with the plastic bumpers, side cladding and a more streamlined shape.   The W116 is pure classic with lashings of chrome.   Even though there is not much in it, the W116 looks long, low and mean.    It has nice touches like the fully chromed door handles.     The double bumper bars are polarizing to some, and date the design, but add to the classic look.      They are both extremely handsome cars, and look good in both the colours here. The W126 is timeless, but I do enjoy the classic look of the W116.

Both cars have attractive alloys, but when hubcaps are specified, the W116 wins hands down.   Those plastic hubcaps on the W126 are not nearly as classy as the painted W116 hubcaps.

Practicality

This is one where the W126 wins hands down.   It is a much more feasible proposition to run a W126 as a daily driver than it is for a W116.    The W126, especially the second generation is much better for rust than the W116.   Even W116s that have been garaged all their life still develop rust in various areas, and cars kept outside disintegrate before your eyes.      The W126 also has ABS as standard, and better A/C.     The W116 was available with ABS from mid 1978, but it was never offered by Mercedes-Benz Australia.

The interiors of both cars are equally hard wearing, given they are both MB-Tex.     Later 300SEs were standard leather and they can be hard to find with decent interiors as few owners conditioned the leather.    The W116 suffers from a lack of rear legroom, wheras the W126 short wheelbase is about the perfect size.      The W116 has a noticeably better turning circle than the W116.   The seats are also more comfortable on the W116.

The W126 is lighter, and has better aerodynamics so has far better fuel efficiency.   The second generation cars in particular, as KE-Jetronic is more efficient than K-Jetronic.

Parts availability is also better for the W126, although its a more complex car with more to go wrong.

Driving feel

The W116 is slightly better here.   It feels a bit more connected to the road and gives you more feedback.    The advantage of the W126 is that its far quieter on the motorway.   The extra aerodynamics really pay off here.     The wind and engine noise in particular are much less noticeable.    In some ways the W126 is too quiet, you can’t really hear the engine at all.    The W126 is also softer – you can feel the influence of the American market on how the car is set up.

The W126 is much lighter, the 300SE in particular.   An early car like this weighs in at around 1500kg, meaning you can toss it around roundabouts with abandon.   The W116 is about 200kg heavier.

Generally I prefer the W116 unless you’re doing mostly motorway driving.    The W116 is just more fun, but less refined.     They are both great cars to drive.

Performance

The W126 has the edge.   The M110 never coped well with emissions, whereas the M103 just shrugs them off.    150hp vs 180 is a pretty huge difference, especially with the W116 being the heavier car by a fair margin.   Having said that, the gearing is better in the W116, so the real world difference is not quite as great.

The same is the case with the v8 engines too, so not limited to the six.

Interior

Slight edge to the W116 here.     The W126 took the W116 concept and further refined it.    In some ways its nicer, but in other ways it lost some of the nice little touches, such as the chromed window switches.    The pinstripe Becker radios were some of the classiest of the era.       The W116 instrument cluster is also easier to read, and the seats are more comfortable.    I also prefer the fox eared headrests to the W126 units.     The velour carpet W116s are also nicer than the W116 in that the rears still have proper separate carpets.   On the W126 there is a modern style moulded carpet that doesn’t have the same luxury feel with the soft underlay.

The standard air conditioning controls are simpler than the climate control that was standard on the W126.       The W126 just feels a bit more refined, and has some newer touches in the cabin, such as electric passengers mirror.    It also has a rear passengers vent, outside temperature display and other modern conveniences.

Conclusion – W116 280SE vs W126 300SE

They are both excellent cars and there is not much to separate them.   The W116 has the classic look and a more engaging driving experience.    The W126 is more modern and refined, and bit less connected.     The W126 is far better suited to daily, or semi daily use.    The W116 is probably a better classic. If you can’t decide, have one of each. That is what I did.

The post Mercedes W116 280SE vs W126 300SE appeared first on Classic Jalopy.

I had a look at the car, and saw that while it did have a Hirschmann branded antenna, it was the wrong one.   It was one of those generic antennas sold in the 90s.   Quite a lot of original Hirchmann antennas got replaced with these as they were not much more than the cost of a new mast.   I have one on my 450SLC, as when I got the car the original Hirchmann was long gone.  Sadly, it had been replaced by something cheap and nasty.

Since I planned to sell the 300SE, and I wanted to sell it with a working power antenna, I swapped out the 90s Hirschmann antenna with the proper 80s unit that no longer worked.   Since the 300SE was no longer sporting its original Becker, it seemed like a reasonable swap.    I also had one in the 420SEL parts car.    As the harness had been cut on the 560SEL, I was able to grab that piece of harness from the parts car.

That harness piece let me test both antennas.   The great news was that both of them moved a bit, they just had bent and stuck masts.    I had bought an aftermarket mast to try with these antennas, so I started with the antenna from the 300SE.   It was actually worse, even though the one that came out of the 420SEL was really dirty.    After a clean up they both looked pretty good.    I was pleasantly surprised, as I had low expectations of even having one working antenna from the two.

I set about opening up the Hirchmann antenna from the 300SE.   While you don’t strictly have to open up the case to change the mast, I wanted to inspect the inside and lubricate the gears.  Opening up the antenna case is very easy once you’ve done it once.  You have to release the plastic tabs.  I found the best way was to use a medium sized flat head screwdriver and lever each one carefully from the top.   I tried for a while to push them from the bottom but that never worked.

Overall, I was pretty impressed with the internal condition of the antenna.   It was a bit dirty, and there was a very small amount of moisture inside the case.   That was all cleaned up.    You need to be careful not to lose the little rubber rings that locate the motor.   There are three on the front and three on the back.

The actual process of removing the mast is well covered in various youtube videos.   I found once I had loosened the top of the mast and removed the mast carrier, I had to run the antenna to get the toothed belt out of the housing.   Its possible with one person but would have been easier with an assistant to hold it.   I also had to run the antenna to feed in the new mast.  I went with a cheap aftermarket mast, primarily because I had fairly low expectations that my antennas would work.

The mistake I made first time, was to feed in the new mast fully before re-assembling the housing.   The best way is to feed it in about 80% and then cut the power.   If you feed it in all the way, the motor runs to the end and pulls itself up too far and off its mounting points.   This means the belt doesn’t line up with the bulge in the case to accommodate it.     If you only feed it in 80%, you can then locate the motor properly in the case, check the rubber rings are all located properly, and then put the case back on.   Once the case is on, I then tightened up everything else, and ran the mast up and down a few times to test it.

From there it was a fairly simple matter of installing the antenna in the 560SEL.   I forgot to order a new rubber grommet to locate the antenna in the rear wing.  The one from the 300SE was a bit hard, but generally ok, so I re-used it.    I first spiced in the harness from the 420SEL into the 560SEL, and was a bit perplexed why it didn’t work.   After a few minutes of checking fuses, I remembered that the trigger wire to the old antenna was separate.  It wasn’t using the blue wire from the factory harness.

I suspect this is because the Becker 868 is a two piece unit, and the antenna trigger wire comes from the secondary box, which is located in the boot on my car.    I’ve left this wire with a quick disconnect. I often park the 560SEL under the hoist, so it can be useful to disable the power antenna.

I’m going to purchase a new grommet and new genuine mast to have on hand.   The old grommet was quite hard, and I’m not sure how long this aftermarket mast will last.   Now i’ve done it before, it will be a simple job to replace them if I have to.   The car is all ready for a club run tomorrow.

The post W126 Hirschmann Antenna appeared first on Classic Jalopy.

After driving around for a few weeks, I realised I needed to make a few changes.  Overall, I was really happy with the system, except for the following:

• USB charging ports were no longer working
• Distortion in music with strong midrange at medium to high volume
• The radio worked at position 1 of the ignition switch, but the bluetooth module required position 2.

The USB ports were working fine until I put the trim back in, so I assumed I had accidently pulled out the socket during the re-install.    I also figured I could improve the distortion by playing with the amplifier gain settings.    It is never going to be distortion free due to the small speakers in the car, but I thought I could get it better.

The last one, I assumed I had plugged into the wrong pin on the X30 connector.    To get to all this, the under dash panel, side kick panel and carpet must be removed.   That provides access to the X30 connector and the cover for the various control boxes where I had installed the amp.

Some testing with my power probe quickly confirmed the issue with the USB ports.   The connector between the X30 harness and the US transformer was no longer working.   Instead of just replacing it, I added another 20cm of wire on both the positive and negative so it wouldn’t be under pressure during the install.

The X30 wiring proved to be a big more complex.   I was using pin 5, which is supposed to be hot in start, run and accessory positions.   I had assumed this meant position 1, 2 and 3 on the ignition switch.   Turns out it means position 2, both when the car is running and when it isn’t, and the start position (3).

I swapped over to pin 1, which is hot at all times.   I didn’t want to create a drain on the battery, so I left the USB cables on pin 5, but harness for the radio accessories is controlled by a relay.   The relay is energised by the antenna signal from the radio.   That in turn switches on the amp, triggers the antenna and powers up the Tranzit Blu.   Given the presence of the relay, it should not be drawing current with the car off.   The only thing that is actually using power is the Tranzit BLU, which has minimal power needs.

Next was to look at the distortion.   I found that it sounded better with the amplifier gain turned up more.   Probably because the signal from the Becker was from a the line out module.    Since I am using a single left-right input, I wasn’t able to adjust front and rear gain separately.   This is a shame, as the rear speakers are larger.

After driving the car some more, I was really happy with the improvements.   The Bluetooth function powers up when the radio does.   The distortion is much reduced.   And the USB ports now work!

There was one more thing left to do.   Investigate if it was possible to have the music play from my phone as soon as it connects to the Bluetooth in the car.    I wanted to be able to leave my phone in my pocket and it would just play.   The Tranzit Blu has a button to advance the track and answer calls, so the phone is not necessary to control things.

I found there are more possibilities on android.   For an iPhone, there is an Apple app called ‘Shortcuts’.   This allows simple if/then/else logic to automatic various functions.

The left hand screenshot shows how simple it is to create the function.     Unfortunately, it does not run without any user input, as the script generates a pop up that asks the user if it should run.    This is better than going through the menus on the phone to select music, but not ideal.   The popup is shown on the right.

The installation is now complete.   I’m really happy with the outcome.  I have the look and feel of the original Becker, with the Bluetooth FM injector for modern functionality.

The post W126 Becker Radio install – part 4 appeared first on Classic Jalopy.

The first step was to properly organize and tidy up the wiring.  I wanted a neat install, and to hide all the wires out of the way.   The Alpine amplifier I am using is small enough I could tuck it in with some other control modules in the passengers foot well.

I mounted the amp with the back face up so I could adjust the dip switches if required.   I didn’t have a great way of mounting it without drilling, so I used some stick on Velcro.     Before I re-installed the under dash panels, I had two further tests to perform.   The first was to check the hands free calling feature.   Last time I was testing the system, it was after 11PM, so it wasn’t really appropriate to start calling people.   I’m glad I did, as the previous microphone from the Alpine head unit did not work with the Tranzit BLU.

The Tranzit BLU comes with its own microphone, but I had planned to use the Alpine mic as it was already installed.   That meant I needed to remove the radio to feed the cable for the microphone to the drivers side of the car.   In doing that, I discovered a problem.   I had cable tied the RCA cable to keep it away, so when I tried to pull out the radio there was no slack in the cable.

Something had to give, and that was to pull the line out module off the back of the radio.   It has a screw holding it on, but only one.   That mean it levered outwards and bent one of the pins.   Luckily I was able to remove the module, bend the pin back, and re-install it.   It also meant I had to cut off all my cable ties, add more slack and then re-cable tie that section of the install.

My second test was to try the high pass filter for the rear speakers.  In the end I set it at 60Hz.   With that done, I was able to start putting things back.

The plastic retaining screws for the cover for these control boxes were long lost on my car.   Luckily, the parts car had one of them which I used.   One of the connectors for the Tranzit BLU was loose, so I sniped it off and replaced it.

The two side panels were quite easy to re-install.   The one against the console just slots into place.    The panel against the side of the car slides in from the rear.   It is then further secured by the screws for the bonnet release.

The hardest panel to re-install was the passengers side under dash panel.   Getting that back into place was a real pain.   I set it up so the USB ports were just poking out between that panel and the console.   That leaves them accessible for my phone in its windscreen mounted phone holder.

On the drivers side, the under dash panel was easier to use.   I noticed when putting it on the ‘scoop air’ vacuum pod was damaged and needs replacement.   These are now NLA, but diaphragms are available from aftermarket sources.   That will be a job for another day.   let the control button just poke out on the opposite side to the USB ports.   I also had the microphone coming out on the other side of the steering wheel.

Once I had the radio installed, I took the car on a test drive to see how it all worked.   Overall I am really happy with my Becker radio install.   Now I have the Becker installed, its obvious how out of place the modern Alpine head unit looked.   The Tranzit BLU is a nice way of bringing a period radio into the 21st century.   I prefer it to modifying the radio to support Bluetooth.   I plan to keep this car for the long term – and who knows how long Bluetooth will be the primary technology used for this type of streaming.    The sound is very good through the amplifier and I was able to adjust the bass/treble controls on the Becker 1402 to my liking.

Through my testing, I have found two issues I will need to address.   Firstly, the USB ports are now no longer working.  I suspect re-installing the under dash panel pulled out a connector.   This is a pain because it was the hardest one to get in.   Secondly, the Tranzit BLU is not powering on when the ignition key is in the accessory position.   It only works in start and run (i.e. position 2 and 3).    I neglected to do testing in the accessory position which was a bit of a miss.   The problem is likely that I have a pin in the wrong spot connecting into the X30 power block.   I have to take the dash panel out anyway to fix the USB ports, so I will look at this at the same time.

In a totally objective view, I’ve spent hundreds of dollars on my Becker radio install to have less functionality than before.    I don’t see it that way though.   The Becker works really well in the dash of the W126 and with my improvements, I have a system I really like.

I’m going to use this system for a while before I move onto my next Becker radio install and upgrade – on my 450SLC.

The post W126 Becker Radio install – part 3 appeared first on Classic Jalopy.

I decided to use two X30 harneses for the install.  I had four available plugs on the X30 power block, so it kept it neater if I used two.   The main purpose of the first one was to connect my USB ports.   I also used one of the ground wires for the Tranzit BLU.   For this application I only needed pin 5 and pin 1.   I removed the wire for pin 3.   The USB ports will be available when the car is in the accessory position, starting or running.   I thought about making them live all the time, but I am not sure of any minor current draw from the USB port module.   As this car is not used daily, I don’t want any current draw.   No more driving around with the ashtray hanging open.

The nice thing about this setup, is that I can simply unplug the module if I ever need to.   The ground wire for the Tranzit BLU will have a plug for the same purpose.    The second X30 harness will power the relay which controls turning on the amplifier, and powering the Tranzit BLU.   I don’t want the Tranzit BLU running with the radio switched off, as my phone will pair with it and it will be useless.   The relay will be triggered by the wire from the Becker that normally controls the electric antenna, but the relay will now fire all these things.   The amplifier has a trigger wire for a second amp or antenna, so I will use that one for my power antenna.

I originally cut this harness shorter as the length required is only from the X30 power block to the footwell.   I forgot that the wires from the X30 exit forwards, so I had to join it back together again.   In any case, I now have the X30 wiring in place and two spots remaining.

I mounted the relay in the passengers foot well using an existing screw.  It was probably for the previous Cobra alarm.   Next step was some basic tidying up of the wiring so I could see what I was working with.   That meant using some cable ties of the various wiring groups like front speakers, rear speakers, relay triggers etc.

To test the system, I needed core power to the amplifier.   There was still a wire from the battery to this area of the car from the old Cobra car alarm.  I was able to repurpose it with a new 15A inline fuse.   Once done, it was a fairly simple matter of plugging the various connections together for a test of the system. Before that test, I had to configure the amplifier.   There are some dip switches on the back where I set the input for two channel.   I also turned on the high pass filters – for the test I used the 60Hz option for the fronts and the 80Hz option for the rears.

Powering it on, it all seemed to work properly first time.   Normally when I do projects like this, there are issues I need to address.    Before I paired my phone, I was able to listen to the radio as normal.   Once I paired my phone I was able to play music through the system.   It sounds pretty good!  I adjusted the gain levels slightly on the amp while testing a wide variety of songs.   I also wanted to make sure the left/right speakers were installed properly.   Queen’s Bohemian Rhapsody is useful for this.   The small button used to control the Tranzit BLU also worked correctly.   When in music playing mode, pressing it advances to the next track.   By now it was 11:30PM, so I didn’t test the handsfree calling function.

Since the music from my phone is going through the FM signal, its not perfect.   It is very good though, thanks to injecting the FM signals right into the antenna cable.    The Alpine amplifier means the Becker is easily able to power four modern speakers.

The USB ports were also working correctly and powered my phone without issue.

Next steps from here is to mount the amplifier properly and tidy up the wiring.   I may also play with the high pass filter a bit more.   80Hz might be a bit ambitious for the 6.5″ rear speakers in a W126.   Then all the trim needs to be re-installed.

The post W126 Becker Radio install – part 2 appeared first on Classic Jalopy.

My first task was to research the radios and purchase a suitable unit.  I ended up purchasing two radios,  Becker 1402 and Becker 1480.   As the skills and parts to repair these radios are getting harder to find, I wanted a primary radio and a backup unit.   I am installing the 1402 and will get the 1480 repaired and keep it as the backup.   I have tested the 1402 and it works well.   To connect the radios, I also had to purchase the correct Becker plugs.  The wiring harness had been cut for my car.   These were not cheap.  I was lucky enough to be able to grab a backup set from a USA junkyard.

Secondly, I wanted to keep the modern speakers I have in the car and not rely on the factory fader.  I researched and purchased the factory line out module so I could use RCA plugs to connect a small amplifier.   This also worked well on my test bench.

Thirdly, I wanted a solution to play music through my phone and have hands free calling.   I’m using the  iSimple Tranzit BLU HF which essentially piggybacks off the antenna cable and provides an FM signal directly to the radio.   That also worked well on the test bench.

Finally, I wanted to add some USB ports for my phone so I could drive around without the ashtray hanging open all the time.   I found some simple 12v to USB adaptors for this purpose.

In addition, I wanted to connect up to the car in the least intrusive way possible.   I researched the X30 power block as the way to do this, and experimented with my parts car.

With all this done I had finally planned my W126 Becker radio install and I was ready to start.

The first task was to remove the current Alpine radio.  This was easiest with the ashtray removed.   While the installer had cut the original wiring harnesses, they had used bullet connectors to splice in the Alpine.   This made removing it far easier.   The W126 electrical troubleshooting manual is really helpful here, as it outlines the colours of the original wires so they can be cross checked.   For the main Becker wiring harness, I also used bullet connectors since one half was already there.    This was the ground, switched power, constant power and illumination.

I had a few problems with the illumination.   At first when I plugged the Becker radio in as a test, the screen was garbled.  I used my power probe to check that I had the right wires, and I did.  Turns out the connector as a bit loose and a new bullet connector solved that problem.

I had already removed the left under dash panel, carpet, and the cover for the various control modules to check for the X30 power block.   I also found it easiest to remove the side panel from the console as well.   Once this was removed, I noticed the rats nest of old wiring for the long defunct Cobra car alarm.    The alarm is a Cobra 5801.  There wasn’t a great deal about this alarm on the internet, but I understand they were a high end alarm in the mid 90s.

I carefully removed as much of the Cobra wiring as I could.   I am pretty sure the Cobra would have been equipped with an immobilizer, so I didn’t want to render the car immobile.   In the end I removed most of the under dash wiring and a small control box.   I didn’t touch the other wiring around the window switches, which I assume was Cobra related.   There is still a big green bundle of wires next to the console that I ended up leaving alone.   As I cut/disconnected each group of wires I test started the car in case I had to plug something back in!

I decided I was going to locate the amplifier in the passengers footwell.  There is room down there next to one of the control modules that is populated in later cars.   I think there may be an airbag module there or something like that.    It’s right next to the X30 power block, there is a line from the battery previously used by the Cobra, and its close enough to the speaker wires.

The Tranzit BLU unit will live behind the radio and the ashtray.  I originally wanted to put it down the the amp, but antenna cables don’t reach that far.   In any case, it is very small – about the size of a pack of cards.  It fits quite well there.

Generally the speaker wires were fairly straightforward, but one of them was reversed.   Speaker wires normally have a solid colour for positive and a black stripe for negative.  In this case, the solid colour wire coming out of the radio was going into the striped speaker wire.  I presume it was wired in reverse at the speaker, but I don’t want to check.   The rear speaker covers in the W126 are very brittle at this age and there is a decent change I’ll break it if I attempt to remove it.    I don’t think its a mistake, as the male/female pairs of the bullet connectors are reversed to prevent incorrect wiring.   In any case, I now have the speaker wires plugged into the harness for the amplifier.   I also pulled through some RCA cables to connect the Becker to the amp.

As well as the power cables, and the RCA connection, the becker has a provision to trigger the automatic antenna.    I also want to use this to trigger the amplifier to turn on, as well as the Tranzit BLU.    It would have been simpler to just wire the amplifier and Tranzit BLU to switched power.   However, I don’t want my phone pairing with the Tranzit BLU when the radio is turned off.   It also seems more efficient to do it this way.    I’m a bit wary of plugging three devices into this trigger, so I am going to use a relay.   I don’t want to overly stress the Becker radio.   I’ll place the relay near the amplifier,  so I have lengthened the antenna trigger wire and the wire from the Becker’s antenna trigger port.

The USB ports will be wired directly to the X30 power block.   I’ll use pin 5 for the positive (hot on accessory, start and run) and the ground.    I’ll also use this as the power source for the relay.

My next step is to finish installing the amplifier and the Tranzit BLU.   I’ll then be able to test it, and check the amplifier settings before I tidy up the wiring.   The final step of my W126 Becker radio install will be to wire in the USB ports.

The post W126 Becker Radio install – part 1 appeared first on Classic Jalopy.

The second generation W126 wiring harness provides a factory way of adding additional accessories.   This is the X30 power block.   Up to 8 accessories can be connected using factory plugs and their own wiring harnesses.   The number already connected will depend on options installed on the car.

Other than the direct power for the amplifier, I plan on using the X30 power block for the rest of the accessories.     The x30 power block provides five pins, each with a specific purpose.

1. Hot at all times:   Power from fuse 15 (8 Amp)
2. Hot in run or start:  Power from fuse 8 (16 Amp)
3. Ground
4. Illumination.   This is for accessories that have a small bulb activated with the headlights
5. Hot in accessory, run or start:  Power from fuse 19 (16 Amp)

This provides pretty much all the options required when installing a standard accessory.   Obviously something that draws decent amperage will need a direct connection from the battery.   These fuses are shared with other features.

For the amplifier, I’ll probably just use the ground.   I’ll take constant power directly from the battery as it requires up to 15 amps.    For the USB ports, I’ll want to use pin 5 and pin 3.    For the FM injector, I’ll trigger it from the radio, but use pin 5 for its actual power source.    I shouldn’t need pin four, unless I can’t locate the standard illumination wire for the Becker radio.

The electrical manuals I have for the W126 are for the USA versions.   The core manuals do a fairly good job of covering other models too, but the electrical manual is quite US specific.   According to that manual, the X30 power block is available in the diesels, 420SEL and both 560 models between 1986-1987.   For 1988 it was only installed in cars that had heated seats.    In those years many standard accessories were now hard wired in.

This explains why the 1988 560SEL I grabbed two X30 harnesses from only had the two.  One for the front heated seats and one for the rear.  Earlier cars would have had more.

Since the 300SE/SEL models were not offered in the USA until 1988, I am not sure if the 86-87 models were standard with the X30 power block.  In any case my 560SEC is an 1987 and has heated seats, so the X30 power block should be installed.    I guess it was cost cutting that removed it for later years.

My other complication was that I didn’t know where the X30 power block was located on right hand drive cars.  On left hand drive cars, its under the dead pedal in the drivers footwell.   This location is specifically referenced in the manual.

Luckily I had my 420SEL parts car to use as a guinea pig to search for the X30 power block.   As a 1987 model it should have one.   The first place I looked was under the dead pedal.   I figured if it was in the same place for RHD and LHD cars the manual would have said it was on the left hand side of the left hand footwell.    It wasn’t.

Next place I looked was where the dead pedal would be if my car was LHD.  I had to remove the under dash panel, the bonnet release catch and the trim piece under it.   It was worthwhile using the 420SEL as a test, as I broke the plastic retaining clip trying to remove it on the 420SEL.   That gave me an opportunity to examine it further to ensure my removal didn’t break it on the 560.

Sure enough, the X30 power block was in pretty much the same spot on LHD and RHD cars.   Its an ideal location as it’s right next to the conduit going to the rear of the car.    Not only was it there on my 420SEL, but three accessories were present.   The cover was also still there and not broken.   Great to have as a spare.   The photo above shows the X30 power block with the trim removed on my 420SEL.  It’s the tall rectangular thing in the centre of the photo.    The photo below shows the cover off and how the accessories connect.

That gave me the confidence to locate the X30 power block on my 560SEC where even more accessories were plugged in.    I also found a rats nest of old wires for the previously removed car alarm.   I plan to clean this up as part of this installation.

The X30 power block provides an easy way to install additional accessories on your W126 should it be present.  I understand it is also present on some W124s as well.  It means no alterations to the factory wiring harness are required.

The post Locating the W126 X30 power block on RHD cars appeared first on Classic Jalopy.

The S-Class was officially launched in 1972 with the introduction of the W116.   2022 is 50 years since that launch, and also 50 years since the founding of the Mercedes-Benz club of NSW.   With both of those anniversaries in mind, the Club held a special event to commemorate the S Class.   Of course, holding an event like that begs the question, what is the definition of an S-Class?   The W116 did not open up a new category for Mercedes-Benz like the W201 did.   It was a continuation of a series of models in their range.

In most years, the S Class (or predecessor) consisted of a four door saloon and a coupe.   Occasionally, there was a cabriolet as well.    The Mercedes-Benz archive lists the following models for the S Class and its predecessors.   They trace the lineage back to 1951.

The inclusion of the W188 models is surprising to me.    It makes sense to me not to include the models that sat above the S-Class like the Adenauers, 600, Maybach etc, so why include the two door derivatives?  It just seems inconsistent.   Some will question the inclusion of the C107 SLC models.   While they were based on the SL, they were clearly meant to fit the two door S-Class spot in the range.   The same goes for when the two door cars were branded as CL’s in later years.

Based on this list, the MBCNSW had a great representation of the range on display.   The club tried hard to get cars that are rarely seen at events to come along and did a pretty good job.   In reviewing the number of cars in the club, I’m actually surprised how well represented some of the older models are.   The survival rate of cars like the Pontons and W111’s is pretty good.

It was hard for me to choose which car to bring to this event.   In the end, given the impetus for the event was 50 years of the W116, I decided I needed to finally get the W116 280SE I have been fixing up on the road and at a club event.   Despite finishing at 1AM the night before, I managed to get the car prepared, and ready enough for this event.   This was only my 3rd time driving the car and the first more than a few kilometers from where I live.    While I have more work to do, I was impressed with how the car went.

It was also interesting to look at the model mix of the W116s on display.    There were 11 cars, and I managed to catch the model of 10 of them.    There was not a single D-Jet or carburettor car on display.   All the cars were from 1976-1980 and most of them were 450’s with 3 SELs and 2 SEs.  In addition there were two 6.9s, a pair of 280SEs and a 280SEL.     This trend was mirrored in the W126 models were most cars on display were second generation – with the 420SEL being the most popular.    However at least on the W126 side there were a few very nice series 1 models in attendance.    The story was pretty similar on the W108 models with most of the cars being late production.    It’s clear that the later cars with larger engines are favored by buyers and more likely to be saved.

I really enjoyed the day.   My ideal Mercedes garage is a two and four door model from each of my favourite generations (60s, 70s and 80s).

In past year, the S-Class has been the cornerstone of the brand.   Today, the company sells far more SUVs than they do cars, but the S-Class is still king of the hill.   I wonder for how much longer?  Not sure they would even make it if it wasn’t for the Chinese market.

The post 50 Years of the Mercedes-Benz S-Class appeared first on Classic Jalopy.