First the lock actuator did not work, now also the window will not operate on the left rear door. Strange, when the door is open, the window will operate up and done. I'm thinking it may be the door's computer module that's defective. Anyone have this type issue and the solution?
Thanks

 

Check harness unclip hose first, view part here: https://www.rbgazonline.top/mercedes...97-a49-p-5.htm if fine pull door panel.

 

Thanks konigstiger! I just looked at the door issue again and with the door open, both the window and the lock work. When I close the door, both do not work. So I'm thinking it may be the harness hose. How do I check it, just pull one end out and see if the wires are damaged.........is there a wiring harness plastic connector inside the hose that may be broken?
Thanks again!

 

Okay, I don't see any obvious defect in the wiring in the door jam boot or the electrical connector inside the door panel. So it appears the door control module may be defective. A brand new unit at the MB Dealer is over $300 which is too expensive to buy when it may not be the issue, even with my 10% MB Club discount. So I found a used one on eBay for $25 that the seller states has been tested as working. Part was taken from the same year and model as my 2003 E500. Figure it's worth a shot to see if this fixes the problem. By the way, there are numerous YouTube videos available on the procedures for removing MB W211 door panels........only four torx screws, one small screw on the plastic door lock plate, plus numerous plastic push pins around the door cover to pry out . One of the videos states to disconnect the battery first to ensure the door airbag doesn't accidently inflate although they don't do so in their video.

 

So wait, you're manually locking/latching the door lock actuator with the door open, then unlocking the vehicle and it works?

if part numbers are identical left to right door for the modules, i would swap them first.


I just can't grasp as to why with the door open those items work. If a module is bad, it's bad. Your complaints are intermittent. If neither the door lock or window didn't work at all it would be easier to grasp. But something seems off to me haha. Maybe the module needs a software update or re-scn coding...

but for 25$ module i suppose shotgunning it isn't that bad!

 

The part numbers for all four doors are different (actuators and door control modules).........you need the specific ones for the left rear door. Besides, while I now know how to take the door panel off, it's a pain to take off and reinstall and much easier to just order the $25 part from eBay and see if that works. If that doesn't do the trick, perhaps there's a faulty broken or loose wire someplace in the wiring harness, hard to find without removing the wires that come from the door jam to the connector in the door.

Here's what first started to happen over a year ago. After unlocking the doors, the left rear door would "catch" and you'd have to pull the handle again to open it........apparently the door actuator was failing. Then about three months ago the lock wouldn't work at all. I didn't think to try it when the door was open, so don't know. But about two weeks ago, the left rear window stopped working, but discovered by chance it would work when the door was open, but the lock actuator would still not work with the door open. So last Monday I replaced the door actuator ($109.80 with 10% MB Club discount) with a new one. That's when I discovered that now the door lock and window works with the door open but neither does with it closed. So, thus will try the $25 possible solution with the used door computer module. If that doesn't work, I think I'll take the vehicle to my local independent repair shop and let them fix it.

 

Sharing my experience in removing and replacing the door lock actuator in rear left door. Removing the three torx screws holding it in the door was easy but I tried for about an hour to maneuver it out but it kept hanging up. Finally I got it half way out but something was still holding it until something broke off and it came out. You'll see the removed actuator photo that a small piece at the top left is broken off........it curves up from the left along that seam to mate with the other piece.

Then I had the same problem getting the new actuator into position.........I tried all different angles for about an hour. Then it hit me, maybe breaking off some of the section on the new one to match the broken area on the old one might work, and bingo it went right in. I only removed a portion of the plastic from that area. I think it was hanging up on the inside door handle bracket, which probably needs to be removed to get the actuator in or out........more complications. But I used a "quick and dirty" workaround found by chance that's not by the "book" but works. Just sharing my experience if anyone else tries a DIY door actuator removal on left or right 2003 E500.

 

If you already know all of this, disregard. I don't know your abilities so I'm trying to break it down in case someone else comes to this thread.

Troubleshooting questions:
-Do *both* the rear door window switch and driver's master window control switch control the rear window when the door is open? Or only one switch? If only one, which one?
-Do *both* the rear door window switch and driver's master window control switch fail to control the rear window when the door is closed? This implies a power lead is being shorted to ground or the ground lead is open and has no continuity.

The rear door window switch communicates directly with the door control unit. The driver's master window control switch communicates via the two-wire CAN bus. That's why I ask if both or only one work depending if door is open or closed. If only the driver's master control switch fails, that would point to a CAN bus failure (which would require both Hi and Lo wires to have problems; if only one wire is broken or shorted the system will still work). If the rear door window switch still works, that implies a functioning door control module and points toward the CAN bus. If neither switch works, that points toward power shorted or open or ground wire open. In my case, I had a connector that was jammed against the door frame; over the years the plastic and insulation "cold-flowed" from the pressure and one lead would intermittently short to chassis depending upon door position.

With a multimeter don't just check for continuity end-to-end, also check to see if a power connection is being grounded to chassis. Connect to any control or power line (with power off of course), other lead to chassis, and open/close door and see if the control or power lead suddenly shorts to ground. The driver chips used the door control modules have a crowbar circuit in them that prevent damage to the chip if it is shorted to ground so it will not pop a fuse.

I'll see if I can take a look at schematics tonight.

 

Manually latch door and close it as far as you can.

operate both switches while slowly opening door/closing door.

+1 on operating master switch. wouldn't be a switch issue tho since he can force it somehow to work.

 

I took my vehicle to a independent repair shop and they can't find the problem. They installed a new door control module into the left rear door and that didn't work. They state that their STAR diagnostic equipment can't communicate with the door module. I'm going to pass on your suggestions to them but wondering if you have any additional thoughts before I do that?
Thanks
Tom

 

Okay, problem solved..............as some have already suggested it was the wiring harness that traverses through the door hing area. The repair shop said that the harness length is so tight that opening and closing the door stresses the harness and broke two of the wires inside. Thanks to everyones' inputs. And it's so nice to be able to use the door and window again!

 

I had the same problem: left rear door didn't worked correctly.
I read this topic by chance but this solved my problem. Thank you