1999 e320 CAN bus question
 

ok, 1999 e320 that i've had for about a year. since day 1 the left rear window didn't work, the other day the driver seat, window and side mirror all went away. 2 days later the remote locks failed.
after some research into the CANbus system and related module issues, i replaced the driver door module but there was no change.
my question is this: if you replace the bad module do you still need to d/c the battery for a while to clear the CAN bus system?
i d/c'd the battery and now everything works (including the lr window), as has been described, but i wanted to see if it might all stop working or not.
thanks

Going from memory, but the problem may still recur if you didn't get the correct module.

The way I isolated the culprit (it was a rear window module) was to find the CAN hub under the front passenger A-pillar. Then I would disconnect one wire to a module, do a battery disconnect reset, then drive around a few days until the problem recurred or not.

it returned today but in a slightly different order. both front windows, driver seat, side mirrors.....both rears still work as does the alarm.
so i understand, the CAN bus is under the passenger mat. you would isolate one module at a time by d/c one wire then reset the battery and once you get the correct one d/c/isolated the problem will NOT return?
how does one know which wire corresponds to what module?

thanks

g

For some unknown reason the right rear door module always gives trouble on the CAN bus, go there.

Agree there's a high probability it's the rt rear door module.

To your question, after finding the CAN bus connector (see link), you disconnect a wire and see what stops working to figure which goes to where.

https://www.benzworld.org/forums/w210-e-class/1630519-cannot-locate-canbus-bar-here-some.html

i have one so i will try it and see.

thanks for the help gents!

Hello
I removed the door panel (rr) only to find nothing resembling the door module. Can you direct me to the location?
Thanks again
G

In the rear doors, it is attached the window motor.

i dc'd the rr reg/mod but nothing changed. battery reset underway now and we'll see what happens

thx again

After I d/c’d the rt rear window the front window no longer works, which I could live with...,,however, now the auto-dimming rear view mirror and rain-sensing wipers are not working, which truly sucks.

Whenever I encounter instances of mass revolt of varying systems and appliances I first
check the battery compartment for ANY signs of moisture, water, water marks, etc to
rule out body drain passages or failed gaskets. That area is a target rich environment and
convergence of control units (pneumatic, electronics, electrical....)

so now the interior lights stay on for about 10 minutes after i lock the car and the rear courtesy light won't go out until the car is shut off....plus the other issues pop up from time to time