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I think the seat memory module battery drain issues were on the pre-facelift 203s. Even if they do fail that way and drain the battery, there are known fixes out there to convert the 12v constant to 12v switched and issue resolved - but then no convenience entry.
Thanks for the clarification. That may change my thinking on whether to pursue a further upgrade.
I'm finished now!! I just finished wiring in the lumbar controls. After a quick post to an AMG Facebook group today, a 204 C63 driver confirmed that the memory function does not control the lumbar adjustments. With that, I had full confidence to just wire in power and ground to the white connectors.
For a full stealth install, I took a complete fusebox from a 203 salvage car. Some of the fuses are modular, in that you can add the fuse connectors to the fusebox. There are multiple coloured fuse connectors, but they have different shapes and thus only snap into certain spots in the fusebox. For my purposes, I just took one that had a larger wire size to it - probably 12 or 14 ga, as I planned to connect both positive wires from each seat's lumbar controls to the one fuse.
I looked for a factory ground point in the passenger footwell, but couldn't locate one, so ended up using one of the pegs to which the TCU bracket mounts as a grounding point. Didn't take a picture of that though. I ran the wires behind the centre console, near the bottom rear of the heater box by 'stabbing' a 3/8" extension through, with the wire taped to the end. Then it was just a simple connection to the extra fuse connector at the fusebox. Quick test and all six switches work!
Lumbar control section I chopped off the C63 chassis harness, one on each side. Extensions soldered in and wrapped with a bit of fabric tape.
Passenger side lumbar control harness tucked under and to the side, behind the carpet on the side of the centre console. Same dealio on the driver's side.
One of the modular fuse connectors taken off the salvage fusebox. I actually ended up using one of the green ones, not this grey one. If anyone ever goes through the same process, make sure you take a very close look at the fuse connectors as they are at least two styles, they have different shapes where they fit into the fusebox.
Interestingly, I took a fusebox out of a salvage 211 at the same time I took the one from the 203 - but the 211 fuse connectors are different and won't fit into the 203 fusebox.
Here is the salvage green fuse connector in my fusebox, circled. Looks stock!! I just threw in the 7.5A fuse because it was the lowest amp one I have on hand. I'm not electrical expert, if anyone can suggest that I should have an even lower amperage one in there, I'd appreciate any suggestion.
Last edited by Saaboteur; Nov 10, 2020 at 12:36 AM.
More great work. If I find a suitable donor vehicle, I may follow your lead and add the memory function.
In addition to the work you've done, I assume I will need to add wiring between the door switches and the seat memory module. Finding a good donor car that I can dissect and study will be invaluable. I live in a relatively small market and there is only one "pick and pull" recycling firm in my area. They have two yards, and they occasionally have W203's listed on their inventory. I have obtained parts from Car-Parts.com in the past, but I think that taking the parts off the car will be a valuable learning experience.
More great work. If I find a suitable donor vehicle, I may follow your lead and add the memory function.
In addition to the work you've done, I assume I will need to add wiring between the door switches and the seat memory module. Finding a good donor car that I can dissect and study will be invaluable. I live in a relatively small market and there is only one "pick and pull" recycling firm in my area. They have two yards, and they occasionally have W203's listed on their inventory. I have obtained parts from Car-Parts.com in the past, but I think that taking the parts off the car will be a valuable learning experience.
Thanks. If you go the memory route, I think it would be best if you could take everything - door cards, wiring harnesses, memory modules. I'm already having nightmares of the wiring! Easier to just get the small distinct parts, but tying it all together so it works like factory will be the trick. Unless, of course, the wiring is already pre-populated and there are unused portions? Would certainly help to look at a dead car in a yard. Just hope it's hit in the rear and not on the front doors!
Thanks - I am eagerly anticipating installation day.
I should have been more diligent in my efforts to understand and adapt the wiring harness in the seat. The first seat required 7 months. I completed the second in two hours and 30 minutes.
I am awaiting the arrival of the leather dye I need to repair the scuffed areas on the seats. It is possible that the dye will arrive today (Saturday), although the USPS tracking tool predicts a Monday arrival.
The biggest potential remaining barrier is the air bag wiring. I won’t know whether I have the right configuration until I install the seats. Right now they appear to be plug and play, but looks can be deceiving. I may need to ask a neighbor to help me wrestle the seats into the car. The seats are heavy and working in a confined area could be awkward.
can you make the pdf of the wire schemetics for all the wireing?
I am glad the thread is useful. In retrospect I enjoyed this project, but there was a time before I sorted out the wiring that I thought I had two large paper weights. $80 Canadian is a great deal. I paid $300 U.S. for mine and I thought I did well.
My wife’s cousin has a C55. The interior is a step up from that of the C230. I am interested in your opinion about the merits of the C63 seats versus the C55 seats because my original plan was to swap is C55 interior into my car. I would also like to know whether you are able to use the door switches and memory function in your C55 to control the C63 seats. If you can, I may see whether I can source some door cards with switches and add memory to my seats.
By the way, one of the previous owners installed a set of CLK wheels on my car which appear identical to those you use for your winter tires.
can you make the pdf of the wire schematics for all the wiring?
I found a wiring diagram for the W203 seats, but I was not able to locate one for the W204 seats. I have attached the W203 document and a summary of what I learned about the wiring in the C63 seats in the hope that it will help you with your project. It appears that you are attempting to install your seats in a C300/W204. Based on what I learned while I was searching for information on my project, the most difficult issue you may face involves the SRS/air bag system. This thread has some information.
I can also see two of the seat motors in each seat. (I think I can see the motors for the forward/aft seat movement and the seat tilt. There should be a third motor in the seat back that controls the seat back angle.)
On the passenger side, the forward/aft seat motor has four wires - A thicker White wire and three thinner ones that are Brown/Green, Yellow/Black and Violet.
The forward/aft adjustment motor on the driver's side only has three wires - A thicker White wire and two thinner wires that are Brown/Green and Violet
I think that the additional wire on the passenger side is related to the passenger airbag system. The passenger side has a module marked "Occupant Classification Module" that is not present on the driver's side. I'm wondering whether the additional wire does something to position the seat when the air bag system senses that a crash is imminent.
As my next step I'm considering the purchase of some used W204 seat controllers. They are about $40 from recyclers. This will allow me to set up some tests using a 12-volt power source to see if I can assign a function to each wire. (I will use lower voltage for the thinner wires on the assumption that they trigger relays in the various motors.) Right now, I'm thinking that the wires attached to the large white connectors control the three seat motors and the wires connected to the smaller black connector are for the seat bolsters.
I am almost certain that the blue/brown wires are for the seat heaters:
what actual wires do I cut from the actual seat harness to wire up the w204 seat controls??? And also when I order the w204 harness what am connecting it too!!! Please Kevin help me out
I need to know a little more about what you are working with. Does your C300 have memory seats or does it have the basic seat with only the powered back rest?
I only cut one wire when I installed my seats. I used a harness from a W204 with full power/non-memory seats and connected it to the seat switch and the seat motors. This looks like the harness I used. I substituted the two-wire connectors from the non-memory seats for the 4-wire memory seat connectors in the original C63 harness. The connectors are the same configuration, they just have two fewer wires in them. I removed the wires connected to the seat air bags, because in in the W203 the side-impact air bags are in the doors.
I had 30 minutes to work on the seat. I used my multimeter to check out the wiring on the plugs under the seats. I found that:
On the white 14-pin connector:
1. The White wire in pin 8 and the Black/Yellow wire in pin 9 have continuity. They appear to power the forward and backward motion of the seat.
2. The White/Black wire in pin 10 and the Blue/Black wire in pin 12 have continuity and appear to power the rear tilt of the seat bottom.
3. The White/Blue wire in pin 13 and the Black/Red wire in pin 14 have continuity and appear to power the front tilt of the seat bottom
On the black 6-pin connector:
The White wire in pin 2 and the Brown Wire in pin 6 have continuity. I cannot tell where they go, but I’m wondering whether they power the seat back tilt.
Tomorrow night I’m planning to use the power source I salvaged from a personal computer to apply 12-volt power to each of the circuits I identified and see if I can get the motors to move.
is this the color scheme for the controller I just don't know what part of the seat harness to connect to the controller
I need to know a little more about what you are working with. Does your C300 have memory seats or does it have the basic seat with only the powered back rest?
I only cut one wire when I installed my seats. I used a harness from a W204 with full power/non-memory seats and connected it to the seat switch and the seat motors. This looks like the harness I used. I substituted the two-wire connectors from the non-memory seats for the 4-wire memory seat connectors in the original C63 harness. The connectors are the same configuration, they just have two fewer wires in them. I removed the wires connected to the seat air bags, because in in the W203 the side-impact air bags are in the doors.
my stock seats have no memory and the controls are on the seat same as yours. I am getting a 12v power supply today so I can find the wires you used to test the seats. I am so excited.... if possible. Can we video conference when I am completely set up and can show me exactly what to cut and exactly how to connect my harness I will more than appreciative and I will pay for your time
my stock seats have no memory and the controls are on the seat same as yours. I am getting a 12v power supply today so I can find the wires you used to test the seats. I am so excited.... if possible. Can we video conference when I am completely set up and can show me exactly what to cut and exactly how to connect my harness I will more than appreciative and I will pay for your time
+
I am willing to video conference and there is no need to pay me for my time. I sent you a PM with my telephone number. Please feel to call me during day time hours on the East Coast to set up a time for a conference. Please note the history of this thread. It literally required several months for me to figure out how to make the seats work in my car. I am definitely not a car wizard.
Please understand that I am not a mechanic, engineer, lawyer, doctor or member of the clergy. I'm willing to share what I know, but it may be less than you need. Any advice you implement is at your own risk. I am particularly concerned about the operation of the side impact air bags. The C63 seat air bags are deactivated in my car, but the air bags in the doors are still functional. The posts I saw on the W204 forum indicate that some of the people who tried to install C63 seats in a W204 triggered an SRS error. I don't know how to resolve this issue and you may need help from someone else.
Here's something that may help. When I bought my seat switches, the seller had simply cut them out of the seat rather than detaching the switches from the wiring harness. (The connector with the short pieces of wire attached is frequently called a "pig tail.") See post #10 for a picture of the connectors attached to the switch.
Pig tails for seat switches.
If your switches did not come with pig tails and you decide to use the harnesses already in your C63 seats you MAY be able to match the colors of the wires on the pigtails to the wires on the white connector and be able to control the seat motors. Post #8 (which is copied on post #58) shows the wire colors for each of the pins on the seat connectors. With some experimentation you should be able to figure out exactly how to connect them. Then you will need to remove the wires in the seat connectors from the connectors and attach them to the connectors that insert into the seat switches. You may need to solder on some extension wires to have enough slack in the harness to work with. I did not use this method in my installation, but it should work.
One of my Christmas break projects was to convert the C55 seats into furniture. That turned into a January project, but now I'm nearly finished.
I had some lengths of rectangular aluminum tubing cut, then it was just a matter of drilling holes and bolting everything together. I did acquire some ready made furniture legs off Amazon. I am presently waiting for some plastic caps to put onto the tubing ends.
I had to manually trigger the seat motors forward and aft, and seat back tilt to get the seats positioned where I wanted them. The pin assignments for the C55 seats seem to be identical to the pin assignments for the C63 seats. An obvious exception is the movable headrest on the C55 seats, which the C63 seats do not have, and I don't think Kevin mapped those out. Anyway, the general similarity begs the question as to why the 204 memory modules didn't work in the 203, but perhaps it's the headrest that is the difference. That said, some 204s have memory modules, so it would be interesting to cross reference a C63 with a more regular 204 C-Class.
Only one pictured, but that's just because I haven't figured out where to put the other one in the office yet!
Next will be to finish off my 997 office chair project!
Nice work. I have a back seat that I removed from my car when I installed fold down seats. I've tried to sell it, but I don't have any takers. Maybe I can make it into a couch.
Your discussion of the memory module rekindled my interest in adding the memory function to my car. I still have the memory modules from the C63 seats. I'm not sure that they can be made to work in a W203, but I may be able to puzzle it out by trial and error. It could be that the signals sent from the controls on the door are different and the C63 seat module cannot recognize the instructions. I've watched a few videos on communication over the CAN bus. I don't understand it yet, but I'm persistent and I may eventually take enough time to learn how to adapt the modules so that they can communicate.
I've also been checking the inventory of the local pick a part to see if they have a W203 that might have the door trim with the seat controls. I've found some on Car-Part,com but I would prefer to remove the components from the donor car myself so that I can see how to install them in my car.
i picked up some c63 seats with the idea of swapping them into my 2002 ML55 AMG. ive fabricated steel adapter plates for the seats to fit into the truck correctly but the wiring has been really daunting and as ive got ZERO experience when it comes to this kinda stuff and the project has stalled.
this thread has made my head hurt, however it has reignited my motivated to finish this swap.
do you think id be able to modify the C63 Wiring harness to the ML55 seat module?
here are some pics of what im dealing with.
test fit what im working with ML55 seat module and controls lead that from the ML55 to the Seat Module
I usually start with the idea that anything is possible, but add the caveat that at some point I need to assess the value of the expected benefits relative to the price of investment in terms of time and money.
As you can tell from this thread I ran down several blind alleys before I developed a solution. Please don’t think I have any magic power that makes C63 seats obedient to my commands.
It appears that you are facing a more complex task than mine. My overriding concern is to avoid advising you to do something unsafe. When I started my project, my mechanic cautioned me to (1) avoid detonating one of the side impact air bags in the C63 seats when it was in proximity to my head and (2) don’t inadvertently disable the supplemental restraint system. With that in mind, be careful with any yellow wires and connectors.
I don’t expect anyone to offer step-by-step instructions for this. My approach would be to attach a multimeter to each of the connectors coming from the seat controls one at a time and then operate the seat controls. This would allow you to see whether you can map out which one controls each seat function. You could then develop some kind of crossover between the existing seat controls and the motors on the C63 seats.
I usually start with the idea that anything is possible, but add the caveat that at some point I need to assess the value of the expected benefits relative to the price of investment in terms of time and money.
As you can tell from this thread I ran down several blind alleys before I developed a solution. Please don’t think I have any magic power that makes C63 seats obedient to my commands.
It appears that you are facing a more complex task than mine. My overriding concern is to avoid advising you to do something unsafe. When I started my project, my mechanic cautioned me to (1) avoid detonating one of the side impact air bags in the C63 seats when it was in proximity to my head and (2) don’t inadvertently disable the supplemental restraint system. With that in mind, be careful with any yellow wires and connectors.
I don’t expect anyone to offer step-by-step instructions for this. My approach would be to attach a multimeter to each of the connectors coming from the seat controls one at a time and then operate the seat controls. This would allow you to see whether you can map out which one controls each seat function. You could then develop some kind of crossover between the existing seat controls and the motors on the C63 seats.
Your work is impressive though - I have a 2008 C300 without memory seats and want to do this swap - the fact that you were able to get these seats operating in one package is impressive (you didn't have to worry about coding/wiring for door switches).
Your work is impressive though - I have a 2008 C300 without memory seats and want to do this swap - the fact that you were able to get these seats operating in one package is impressive (you didn't have to worry about coding/wiring for door switches).
Thanks.
I was inspired by Saabatour's work and decided to add the memory function to the seats. I have the driver's side working and plan to have the passenger side working in a few days. (I was delayed because the passenger side needed an additional part.) Memory Seat Function
I think you will have a greater challenge installing C63 seats in a non-AMG W204 than we had putting them in the W203. I recall seeing a thread that included a discussion of a problem with the Supplemental Restraint System caused by the active head rest function in the non-AMG W204.
Good luck if you decide to move forward, but be wary of the possibility that you might affect your SRS system.
I was inspired by Saabatour's work and decided to add the memory function to the seats. I have the driver's side working and plan to have the passenger side working in a few days. (I was delayed because the passenger side needed an additional part.) Memory Seat Function
I think you will have a greater challenge installing C63 seats in a non-AMG W204 than we had putting them in the W203. I recall seeing a thread that included a discussion of a problem with the Supplemental Restraint System caused by the active head rest function in the non-AMG W204.
Good luck if you decide to move forward, but be wary of the possibility that you might affect your SRS system.
Yeah the plan with that is to pull the modules from the original headrests, somehow wire them up and stick somewhere in the C63 seat.
What about the airbag in the side of the C63 seat? Are these working in your W203? I'm not sure if the W203 had an equivalent from the factory - if so where they plug and play?
I was inspired by Saabatour's work and decided to add the memory function to the seats. I have the driver's side working and plan to have the passenger side working in a few days. (I was delayed because the passenger side needed an additional part.) Memory Seat Function
Memory function is cool but to be honest not something I really need/want.
What about the airbag in the side of the C63 seat? Are these working in your W203? I'm not sure if the W203 had an equivalent from the factory - if so where they plug and play?
I deactivated the airbags in the sides of the C63 seats. The process was simple - I didn't connect the wiring for them.
The side impact airbags in the W203 are mounted in the front doors and the C pillars. I had to install an occupant classification module from a W203 into the passenger seat in order to avoid an SRS error. I provided details in post #26. I was fortunate that was the only issue affecting the SRS.
The odd thing about the side impact air bags is that the C63 seats I have had been swapped for a set of W203 C230 seats from a car with a timing chain failure. (The C63 owner found them uncomfortable. I happened upon them when I was picking up some other parts.) The result of the swap would be that the C63 owner had removed the side-impact protection from his front seats and possibly disabled his entire SRS. Virginia has a fairly rigid State vehicle inspection program. I know the mechanic I use for inspection would not pass a car with an SRS error on the dash and I'm not sure how the owner kept the car on the road. The person who sold me the seats said that the donor car had about 60,000 miles on it at the time the seats were removed. The decision to swap in W230 seats into a relatively low mileage C63 seems like it would have seriously diminished the resale value of the C63 or made it very difficult to resell.
Memory function is cool but to be honest not something I really need/want.
I wanted to replace the driver's door panel in my car due to a torn/cracked armrest. I found a reasonably priced replacement with the memory controls on Car-Part.com and the rest of the components were only $62 from a pick and pull. I have now decided to install the passenger side components and the "mission creep" has led to additional costs including the unexpected need to purchase a door control module that supports the memory function. However, the new passenger door panel is a cosmetic upgrade and I
The memory function offered several benefits for me. Because the side bolsters on C63 seats are exceptionally large, putting the seats all the way back when entering and exiting helps to prevent wear on the bolsters. The upholstered parts of seats are wider than the stock C230 seats and it is difficult to jamb my hand between the door and the seat to operate the controls. The controls mounted on the sides of the seats don't work unless the car is switched on. This makes it difficult to adjust the seats after my wife uses the car and leaves it set up for her 5 foot 2 inch height. The door mounted controls turn on when I unlock the doors and I can move the seats to the desired position with literally the push of a button.
None of these shortcomings were issues I couldn't live with. Even if the benefits are minimal, I enjoy solving problems and successful projects are fun.
Many thanks to everyone who shared ideas and to Saabatour for showing it could be done and sending me the wiring harness for the passenger seat.
Aside from the heavy bolstering and lack if adjustable headrest, how do you find the comfort of the C63 seats? More comfortable than your previous seats?
I don't find my standard W204 seats THAT comfortable...and am wondering if being that C63 is a bit more premiun than standard W204 that the ergonomics of the C63 seats are better.
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