DIY: B6 A4 (2002) door latch 'door open' sensor fix
 

Door always open? Mine was. Computer thought my drivers side door was eternally open. This affects not only your ears and sanity, but also the ability to use the key-fob to lock the doors AND affects the use of the alarm system. (it won't work) My friend and I spent almost all day last weekend and fixed the problem.

On the 2002 A4, the sensor module is part of the door latch. However, you can seperate the two. Only problem is - try getting Audi to sell you JUST the sensor. Not going to happen. FYI Audi sells the door latch for $220.00

After a LOT of work, we got the door panel off, and the latch removed. The panel was held in place by several screws:
- 2 or 3 behind the silver trim
- 2 behind the little cover under the handle
- 1 big one at the bottom of the door

Once the door panel was removed, the latch had to come out. This was quite difficult as well. You have to remove the 2 torx style screws in the door jam (be careful not to strip the screw - it's easy and costs $3.00 from Audi, I know...) remove the wiring clip, remove the plastic cover for the inside of the door itself, remove the insulation padding in the door, then reach inside the door and remove the cable that connects it to both the KEYHOLE and the HANDLE.

The keyhole is connected via a funny bendable wire thing that pressure-sits itself into the latch. (this is for anti-tampering for theives) The latch is attached via a hard metal rod. You disconnect the rod by pulling down on the plasic tip, then popping it out.

Then you have to fumble with the latch to get it right out of the door. It's a tight fit. Once the latch is out, you'll see near the bottom of it where the sensor module fits in. There's a little metal clip looking thing that holds it on. Undo the clip, and pull the sensor module out. It's about 3-4cm by 1-2 cm black plasic rectangle that has 2 wires coming out of it.

On the little sensor module, there is a push-pin style button that is depressed when the door is open, or not when the door is closed (may be vice versa, can't recall exactly). The very small pin pushes on a very small spring which completes the circuit. This pin has a rubber cap and IS MADE OF PLASIC - which is why it breaks. (grr) You have to open the sensor module using a very small screwdriver or pick. I replaced mine with a hack-sawed off head-end of a picture hanging nail, covered it with thin hard plasic.

It works great :) :) - That being said, I would not have gone at this if I had known how difficult it was. Even just getting the latch in and out was super hard. If it was on a scale, 1 being easy (like replacing your oil) and 10 being a motor swap, this fix was an 8. I know, cause I've done motor swaps before :)

Attached pics for your pleasure.

PS. The tim hortons was quickly replaced by beer...many, many celebratory beer afterwards

Re: DIY: B6 A4 (2002) door latch 'door open' sensor fix
 

Great write up!