When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Here's my cheap solution to those who may be having the same issue. VCDS reports door contact switch signal is implausible, so just bypass the switch by unplugging it. Watching the VCDS signal showed the bit kept flipping 0 to 1 so there was something up with the switch.
This solution likely causes something else to not work, so do it at your own risk. This solution does help identify if the switch is the issue before you proceed to buying a whole new latch if you wish to do so.
Take off the driver door panel, pop off the plastic cover, and expose the driver door lock assembly. Reach for the 2-wire connector plugged into the A046879 unit and unplug it. That's it. If you short the connectors, then the error will pop back up, so you just need to leave this unplugged.
I taped the exposed connectors on the plug to cover from weather, and then ziptied the plug so it doesn't rattle. High visibility pink ziptie for high performance vehicles.
With this unplugged, the error immediately disappeared from the dash warning, no reset required. A simple thing to try out before buying a whole new latch unit or you could just roll along with it unplugged at your risk. The car still registers door open/closed.
If you want a proper fix and are very handy: after confirming this solution works for you, remove the whole latch, unscrew the 'A046879' module, swap the microswitch inside there, and put it all back in. It's a lot of effort compared to the simpler solution of leaving it unplugged.
Yes, ACC and brake guard error gets cleared and they work again. I can't edit this thread, so here's an update: the problem came back after a few days. So I ended up fixing the switch.
Two screws to remove the unit, I unscrewed it with the door latch still mounted on the car, it's just a pain to realign on the reinstall. The switch unit just comes off by removing the screws.
The switch is covered in resin/epoxy, so I dremelled out the connector points to check continuity with a multimeter.
When the switch operates fine, it connects points (1) and (3). What broke on my unit is between points (1a) and (1).
With the resin removed to expose the contacts, I could solder a wire to join the points to reconnect (1a) and (1).
With the wire soldered, continuity is good between switch and pinout. I filled the cavities with hot glue and reinstalled the switch.
From the 2-wire plug, followed the gray wire to measure the voltage. It now detects 0V & 5V through the gray wire when door latch is flipped.
The second brown wire is ground, no need to measure that.
Currently working fine, will report back if it breaks again.
I'm not 100% sure that this is my problem. I don't have vcds just obdeleven. Tomorrow I will try and to see a live error but even if I don't, I'm going to take off the door panel and disconnect the switch that may be a problem. If I get my adaptive cruise control back by doing that I will probably just buy a new switch from Audi. That will be far less expensive than taking it to the dealership for a diagnostic, paying for their labor and then paying for a part. Either way it goes I would like to thank you very much for your contribution. I've been searching for an answer to this problem for months.
Do you have to remove the exterior door handle in order to get to the A046879? I removed all the interior trim on the door and removed the two bolts holding the assembly in place. However, I still can't pull it down far enough to get it out of the access panel.
No removal of door handle required, the whole lock assembly remains in place. The only part removed is the switch assembly in picture. It's held in by two screws. Unscrew both, and wiggle the piece out of place.
It was a challenge to align back in though, I recall I had to play with the lock by pushing it with a screwdriver before reinstalling the switch assembly. Just make sure door closes and locks before putting everything back together.
Once it's out, you'll know it's the problem by probing with a multimeter to check continuity.
I believe you can test this is your issue by unplugging the connector as mentioned in first post. With car turned on, leave the door open, short the pins together with a wire and then remove the wire. You should see whether this clears the error prompt immediately..
Hello,
I guess I have the same problem as described here. But... My car has soft-close system, so I believe it has different latch.
As you can see in the picture, there's another cup covering 2 important screws. Did you have the same? I didn't try to unscrew that because I didn't know how to do that not breaking something.
One another thing is, that I have 3 cables there. I tried to pin them together and the car showed f.e. opened door while the latch was closed, but the error didn't disappear.
I believe you can test this is your issue by unplugging the connector as mentioned in first post. With car turned on, leave the door open, short the pins together with a wire and then remove the wire. You should see whether this clears the error prompt immediately..
hello thank you for your guide. I do get the error door switch signal issue on VCDS. I removed the switch like you said but the car still reads the door perfectly fine. I assume if i took out the module it should say door open all the time but it does say door closed so no lights for the door for me and the error still does not goes away.
Also i don’t think so this part comes standalone right? Have to buy the complete lock?
even if i manage to find a used module. Do you think i have the same issue?
Followed your guide, worked great! the trace going from the switch to the plug runs directly over a hole in the micro pcb so breaks very easily. Wire soldered across should be a permanent fix! Forgot to take pics :0(
The biggest pain was dropping one of the screws. Would have been much easier if my forearm was 3 inches shorter so it would fit in the door haha
Waiting for my buddy to bring his VCDS over to make sure its cleared :0)
Thank you for the guide!
09-17-2019, 10:35 AM
ACC and Audi Braking Guard fix with switch bypass
