kcscout

Hey guys. My front passenger door control module died on me. After searching for days, I cannot find a replacement (except at the dealer and I am afraid to ask how much they want for one). My vehicle is a 2000 S500. Does anyone have a working DCM to sell.

Thanks

Skylaw

You can also try a breaker yard such as Potomac German Auto (one of the largest MB breakers in the country) - http://www.pgauto.com/. Their online catalog can be tough to navigate - give them a call.

ayayikes

U can also try on ebay.com
Good luck

tiredoffit

I have one for sale, and my too just stopped working. I just replaced my module and even after that, everything in the drivers door is still dead, despite that I checked for power to the Module, and there is power everywhere, so I sill do not understand why it's not working. so obviously there is something else going on. So, before you buy a replacement, I would check if you have power coming into the module, and check the window switches as well, because I have power there too, but nothing is working, the only window what is working is the passenger side. The rear windows don't work either. If I hold my key to the IR in on the passengers door, I can lock the car, I can open and close 3 windows open, but not the drivers door window, so I am in a bind with that one.

kraut56

since most of the door control module only "communicates" digitally via the CAN bus, you need a DAS/SDS read out.

bbirdwell

Going to take a bit of work to troubleshoot and I hope you are good with a multi-meter. Check that ground wires are grounded properly, check that wires that are not supposed to be grounded are not grounded to chassis (this one bit me in the butt on a power mirror problem). Power wires should not be grounded to chassis (will not blow a fuse if powered from the door control module because the half-bridge circuits will limit the current in event of a short). So...disconnect the connectors, ohm out the wire end-to-end to ensure it is not broken, then see if the wire is shorted to ground. A schematic is helpful so you want one of those, too.


If only the window, I'd say the problem is in the door. If nothing in the door works, could be the DCM has power but has a bad ground. Not likely to be the CAN bus unless both H and L broke; the bus will work with just one wire as a fail-safe. Could be just the window motor or one of the wires to the window motor is broken or grounded (the wires reverse polarity so if one is grounded to chassis the window will roll up but not down; the above-mentioned half-bridge drivers will prevent over-current damage to the DCM).

Russell Ormerod

Any fault codes? Check if the unit sw can be updated! Not too sure if it's possible on w220 maybe I am thinking about w221 chassis. Get it on a ads machine first!

tiredoffit

Thanks for your reply Russell. But the DCM does not give any fault codes as far as I know. What boggles my mind is that I have power to the unit, and the circuit board as well, I need to find a schematic whereas I can test where I suppose to have power. I have power to the large black plug on the red wire with a black stripe, next to it is a brown wire, somebody told me that is a ground, which is odd, because usually brown is power and not ground. Next to the black plug is a large white plug, and I wonder if I have to have power to the red wire as well because there is no power to that plug. I have a interesting day ahead of me to try to figure this out. If I cannot find it, then the MB dealer has to put it on the star. I am seriously considering to part the car out, to me the S430 is just a money pit. Having replaced the complete airmatic system I still have trouble, the comp still tells me airmatic visit repair shop, this car drives me nuts.

Thanks

Will.

Russell Ormerod

Sorry about all your issues. But getting back to your DCM. If you have checked the faults to the DCM it means you have communication with it. Meaning power is ok And Canbus is working. As far as colors go brown is always ground on any mercedes you work on. Thick red black is power thick brown is ground. The other wires that are plain red and plain black are output to the window motor. So basically you only need power and ground and canbus. So if Star can see it. And nothing works then the unit has failed

tiredoffit

Well, I have power everywhere, on the DCM and the window switches, on the circuit board, on the mirror switch, there is power to the lights, and yet, nothing is working. Now its even worse, I blew the 40 amp fuse, I replaced the fuse, but there is now no power to the DCM anymore, so I am wondering if there is another fuse somewhere related to the DCM to restore power to the unit. And by doing more research it appears that according to this forum, the DCM lost communication to the Can Bus, so my only way out now is to get it to the dealer and let them diagnose the problem. I have more problems with this car. like the airmatic system, the trunk close assist, steering column, the open and close feature, I have to put my key to the IR receiver in order for me to unlock the car, this car is a mess and I hate every little bit on it. I am crying every day that I sold my 500 SEC and got this car, what a mistake that was. Anyway I appreciate your input and I will keep the forum posted what the star came up with.

Russell Ormerod

All you you need Is power on red black. That's the main power input to the DCM. If that is there. It is very difficult to try and fix a mercedes without star.

tiredoffit

Yes I think so too. There is so much electronics and computers in that car that I'm afraid to even touch anything. So, to the star it is and lets see what those gurus come up with. Depending on the outcome, and the price tag to get it all repaired, I will make the decision to either fix it, or better yet, part the car out. But why is there no more power to the Red/Black wire after I blew the 40amp fuse, replaced it, and still no power came back to the DCM? I don't get it.

Bcbrundle

I know this is an old thread but I thought this could help someone.
So after reading through all these posts about the DCM on my 2000 S500 failing I actually saved mine. To start with, all the lights on the DCM were flashing on and off as were the mirror signals. The windows and drivers seat had a mind of their own not knowing whether to heat up or cool or go up or down. Even the mirrors decided to have an epileptic fit.. Within a few minutes it all stopped with the windows in the up position but non functioning from the drivers door. Nothing functioned from the drivers door. What I did was removed the DCM, mirror control, and window control door modules. I then proceeded to disassemble all three down to the circuit boards and leave them in from of a blow dryer for several hours. I was concerned about the mineral deposits left on the main IC from water so I ran a pin head in between the solder joints to clean the white stuff out. Upon reinstall everything was back to normal. I hope this helps folks in the future. The modules do not deal with water well.

wallyp

True, that! They can easily be damaged during the installation of window tint, but a more common cause is probably over-application of window cleaner on the inside of the glass.

CowboyKid

I think you can purchase an aftermarket from AUTOHAUSAZ.COM. Or try Module Experts in Florida at 904-866-4778. They repair them. Beware of there warranty, They say liftime but wat receipts from a licensed repar facility.

Thanks, good luck.

Cowboy

CowboyKid

I tryed ebay and got salvage yard parts that worked for short time, trying to get better quality!!

Cowboy