Pagz

Hello guys,

I have been chasing problems with my remote locking(RCL),IR(infrared), and drivers side control module(DCM1), I believe this is very common as also had this problem on last w202.

Some times the drivers window and/or IR on RCL would fail to actuate, when checking with SDS shows no CAN with DCM1 and when checking EIS shows CAN high fault , but would always reset when battery disconnected/reconnected and come back at a later stage.

Recently, the whole RCL system failed and left me stranded 3 hours from home, I ended up breaking the window and driving back ( left old mechanical key from C43 EIS in glove box )

Now I am replacing the rear quater window, I decided to do some tests with SDS connected and found drivers side rear window control module is causing CAN high fault, also passenger side causes same fault but is much more intermittent. I tried to unplug other modules on interior CAN whist leaving DCM3/4(rear door modules) plugged in and no other modules correct the fault.

Never did the rear windows ever stop working,but I think the rear door modules are responsible for causing problems with DCM1, I have seen people replace DCM1 thinking it is the problem and still have the same fault!.

I pulled apart DCM3 to see if there was anything obvious,these are not a serviceable part so I have to cut off the plastic around the cct board to allow viewing of all components... there was no evidence of moisture, however some minor tracking from a reaction and the cct board is poorly coated with sealant, I thought maybe carbon or grease from the DC motor might be the cause but it was very clean inside.

After cleaning the cct board I retested and it still causes CAN high fault.

So only option is to buy 2x new DCM3 and DCM4 complete with motor and armature.

Pagz

Good info on this issue here:

http://forums.mercedesclub.org.uk/sh...d.php?t=102564

Cheers,

cm60k

Very good info. Paul,

i didn't know that window DCM's send error to the CAN, is this for late W202 or also for pre W202 also..??

ZAYED,,

Pagz

Hello Zayed,

Yes rear DCM's can be communicated with but I forget which options/alarms they have, I think only late model 98+ have the rear DCM's!.

I have checked mine further by removing capacitors and testing but have so far found no fault.

I ordered a new DCM3 and DCM4 they should arrive soon

Somalia757

Crazy how many little control modules there are to control everything.
Good info

cm60k

Paul,

I think MB combined DCM's with window regulators, smart move, but making lot of headache to us,

i notice these DCM;s made by "NEC", soo strange, this company usually NOT involved with any Auto business,,

that obviously explain why MB combined these with a fully mechanical part..>>>

ZAYED,,

cm60k

Paul,

Did you fix this..?

ZAYED,,

Pagz

Hi Zayed,
I think the part is made up by a few manufactures, the motor has "Bosch" label on the back, but under the Mercedes label you can see in the photo it says "brose"?

I have ordered both DCM3 and DCM4, but only DCM3 has arrived so far, I have installed it and when DCM4 goes in I will test system and post results

While replacing rear DCM's I decided to take out all side windows to clean off hard water,check for rust and repair, replace side window seal covers and outer rubbers and new door liners, replace B pillar covers and install W210 colour coded door handles...the car looks brand new

Pagz

Update,

DCM3/4 now replaced, Interior CAN tests fine with no faults!

To make my CLK55 EIS/Key work with long range RF I have changed over the OCP circuit board from CLK55. you can also just swap the plastic and buttons instead depends on which frame is in better condition, in this case I reused the C43 one.

So now entire locking system works 100%.. can lock from far far away

Note the frequency on the circuit boards.

cm60k

Thankss for sharing this value info. Paul, you always discover great things..

it's great to know some of damn mysterious MB secret's, i think that involve to the ME2.8>>ME2.8.1, not for ME2.0, isn't..?!!!?

ZAYED,,

Pagz

Sure zayed , I maybe have to much spare time

Im not sure if OCP changes with me2.8, I know DCM do update!. Something to be aware of if using donor parts from 210/208 =)

cm60k

Hey Paul, did you find solution on this..?

ZAYED,,

Pagz

Sure Zayed, Since I did this I noticed many 98 - 00 202 for sale with rear windows or drivers window not functioning correctly, people don't usually mention there key doesn't work long range anymore but it probably isn't working also... I can assure you is most likely DCM3/4 faulty and this does not show up in SDS

cm60k

Thankss Paul,

Yeah, good point, i noticed that as well, with my friend's W208 CLK55..

ZAYED,,

202.033

Just to add, I had a 202 come in the shop with this exact problem recently, independent shop replaced both front door modules twice, 4 modules total. Had faults for interior can communication, pulled up can pattern on hermann o-scope and unplugged can connectors from the x30 block in the passenger doorwell, whenever unplugging the left rear dcm the o-scope pattern would go from high side disrupted back to normal. multiple tac technical cases on this issue. point of story is rear door control modules are known for taking down interior can and causing random/intermittent issues with all modules on the interior can.

Ali Nouh

Hi paul ,
I have the same problem with w202 "c 180 1999"
Some times the right door window and the IR receiver in the same door stop working , after disconnect the battery and reconnect it the window start to working again , after many times the right door control dead so i have change it .
the left door IR receiver wasn't work too cause of a damage pin so i change it too "the left door control"
Now everything working fine from close range but the long range it's not working anymore, I'm trying to figure why and i was't know that the back doors have controllers too and maybe that's cause the problem , so i will take a look
thanks ,
Ali

Pagz

Hello Ali, try individually disconnect the rear window winder motors/module and see if your IR works again, It is likely this is the main fault. even new rear door modules will eventually fail. I have a set of rear manual winders I'm going to install manual on my C55 for this reason.