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All - the driver's window on my 2000 E320 Estate has stopped going up or down. I've pulled the cover and tried a new window motor but that didn't work. I can hear the relay click in the door control module when I push the switch on the center console so I don't think it is the switch.
My guess now is that the door control module needs to be replaced. I have a used on on the way ($16 used on ebay vs. $275 new).
I would like to know what the voltage should be on the 6 pins in the plug that connects to the window motor.
Does anybody know what the voltage should be for those pins? The plug is unidirectional with rounded top and square bottom kinda like this:
I don't recall anybody reporting troubles with driver window electrical motor, so you might be the first one on the forum with this problem.
There is not much to motor control. It is 12v going up and 12v going down.
Observe the wires. The thick wires go to the motor, the thinner ones to the counter.
Unlike rear door plastic slider (part of regulator) - the modules fail very rarely.
That reflects the pricing on ebay, where you can find them for 10% of new cost.
No demand = low price on used part.
Second - Check Voltage to Window Motor
The pins are labeled on the plug (see pic).
#1 - 12v constant (Light gauge black/green)
#2 - Switched 12v = window down (Heavy gauge green wire)
#3 - No voltage registered (Light gauge black/red)
#4 - 12v constant (Light gauge black/purple)
#5 - No voltage registered (Heavy gauge black wire)
#6 - 12v constant (Light gauge black/blue)
What I noticed is that #2 (green wire) flashes 12v then goes off when I push the down button. I also hear the click of the solenoid in the controller. It is like a relay trips when I push the down button cutting the voltage. Something is not right here
I assume #5 is the 12v power for up.
I'll now check the switch in the center console and see if I can swap the front left switch and front right switch to see if it is a switch problem.
Ok - this stinks. The window switches are not individual. They are a part of a larger assembly. It doesn't look like I can swap Front Left for Front Right.
Yeah. I could file up switch contacts on W123, when you could replace single switches on W124, but later MB start making digital connectors, where only whole board is available new and can't replace individual part without some soldering.
Still judging from the dirt you have around switches, your car might benefit from new board.
They sell pretty cheap on ebay. I have seen individual switches on European ebay as well.
If it is the switch - you might choose to take MAF cleaner and spray it into the "sides" of the switch while working it back-n-forth - sometimes for a bad/dirty switch a little bit of work will bring it back.
Have you tested your "new" motor on 12V so you know it works - and have you checked the part# of the replacement motor against the part# of the original motor ?
Well the door control module from ebay didn't fix the problem. It clicks on/off just like the original without actuating the window.
I pulled the center console switch assembly and cleaned it out (thanks fabbrisd1) but no luck.
Question - what triggers the 12v cutoff when the window is fully up or down? Basically the window is acting exactly like the others when the down button is actuated when the window is fully down - except that it is up. Is there some measure of electrical load that cuts the voltage to the motor?
I am thinking about pulling apart the passenger door and testing the driver's motor plugged into the passenger's door control module and switch.
The smaller wires going to motor are for counter.
Door module remembers how many turns till the end and turns the motor off.
That is why after disconnecting the battery you have to synchronize as the memory is lost.
Unless you can get your hands on SD computer, the next part in line is the switch... with the board attached.
Ok...
1) cleaned the switch assembly with contact cleaner
2) disconnected the battery for 5 minutes to reset the window memory
No luck
3) disassembled passenger door and tested both the new and original driver's window motors - both work in the passenger side = not the window motor.
Kajtek - agreed that the next part in line is the switch assembly. But I still don't understand how the existing center console switch can actuate the solenoid in the door control module yet fail to deliver 12v to the window motor.
I have looked for a new center console switch assembly but nothing on ebay that I could find for a W210 Estate. There are a few for pre-1999 and most are for sedans and have a trunk switch next to the mirror switch. New part is almost $400......and I'm not even 50% sure that will work.
Might be worth spending a few bucks to have a professional troubleshoot the system with the OEM diagnostics system. Could save you swapping parts blindly.
Scanning would make sense if you can get it for low cost, but paying $150 for dealer telling you "your window motor is not responding" ?????????????
Listen to our "keyboard master Plutoe"
He is never able to solve anything.
With help from my friend Malcolm at Series Motorsport, who is the master at building wiring harnesses, found the problem in 5 minutes.
We decided to start by chasing 12v power from the door control module since it seemed to be getting a signal (at least) from the center console switch.
Clues to the solution can be found in the picture of the connected motor in Post #5 and my test with the volt meter:
"Second - Check Voltage to Window Motor
The pins are labeled on the plug (see pic).
#1 - 12v constant (Light gauge black/green)
#2 - Switched 12v = window down (Heavy gauge green wire)
#3 - No voltage registered (Light gauge black/red)
#4 - 12v constant (Light gauge black/purple)
#5 - No voltage registered (Heavy gauge black wire)
#6 - 12v constant (Light gauge black/blue)"
I was wrong about the assignment about #5 and #2.
#2 - switched 12v is "Up" not "Down" and it registered 12v because was working as it should with the window in the up position - no movement, just 12v.
What I should have noticed is "#5 - No voltage registered (Heavy gauge black wire)"
It should have registered 12v switched.
Then if you look closely at the picture of the plug connected to the motor you see a bit of white insulation poking out around the black wire where it enters the plug.
When we ran 12v directly from the door control module via the heavy black power wire - open circuit. Direct to the green power wire no problem. Confirmed this on the passenger door and black actuated down and green up.
Looking closely at the plug the black wire power wire had a bad crimp. The door had never been disassembled (at least during my last 10 years of ownership), however I knew that it had been repainted when I bought the car. Sooooooo my guess is that the door was hit sometime >10 years ago, the window motor and wiring harness handled roughly, weakened, and manifested just now. Wow
Luckily Malcolm had both the special little tools and a new terminal to rebuild harness plug. Those plugs are seriously overbuilt and getting the broken terminal out of the plug without damaging it was a pain.
That said we were successful and everything is back in working order just in time for my daughter to take the car back to school with her!
08-13-2016, 05:31 PM
