Air bag Module replacement -DIY write-up
Compliments of hartsoe1 @ audiforums.com
Audi A4 B5 Air bag Module replacement -DIY write-up
Airbag Module Change
A4 B5 2000 1.8T Manual
Disconnect neg terminal of battery.
You need the radio code. And the soft code from the current air bag via Vag-com, which is a five digit number, probably proceeded by two zeros. I did this all with VDCS Lite freeware.
Get special keys for radio removal. You need 4 - 2 left and 2 right side. You can see the slots clearly. Just sticking them in, square side towards outside of car, releases the holding clips. Pull it straight out and then disconnect all the plugs on the back and set it aside.
Leave the trim around the emergency flasher alone, you may not need to remove it. If you do, know that it is held on with about 8 metal clips (4 top and 4 bottom) that should release if pulled straight out all at once. I pulled from the bottom first and that caused all the top clips to break from the trim and remain on the car. Super glue to the rescue.
For Center console removal, get in the back seat and pull the ash tray out. There are two 13mm nuts with washers under there to remove. You are now finished in the back seat. (See picture 1).
Get in front seat and pull out double cup holder on center console beside emerg brake and there is another bolt there. (See picture 2) On both sides of the center console vertical section, up below the shifter, is a screw covered with a plastic cap. (See picture 3). Remove and you can pull the center console up and back about an inch or two without removing the emerg brake plastic (I removed my emerg plastic but I don’t know if I needed to). If you need to remove the emerg brake leather handle and plastic fairing, there is a little plastic plug under the leather handle at the rear end that needs to be popped out. My cig lighter was plugged in up near the shifter but you don’t need to unplug it unless you want to completely pull out the center console.
With center console pulled back a little, pry up the shift console at the rear, rounded end. It comes straight up and then pull back. The platform that surrounds the shift hole will now come unclipped. Pull it out from under the ash tray.
Now for the climate control (CC). I can’t remember if there are two screws holding it in at the top, but it will be obvious if they are there. The CC is clipped once at each corner. You can see the brass looking ones up top with the radio out. (See arrows on CC picture). These clips are in grooves/tracks and can move front and back in these grooves. There is a hole in the clip metal seat and if you are lucky you can grab it with a pick or small screw driver and pull it towards you (towards rear of car) enough to essentially pass the clip ridge. With these two up top sort of halfway unclipped, insert a medium sized flat screwdriver in the crack between the CC and cross member above the ash tray on each side and you should get the bottom corners to move out one at a time. (See circles and badly drawn screwdriver on CC picture). Then you’ve got it out.
Remove all electrical plugs, but, the seat heaters are special. The entire module comes out, from the numbered rotary selector all the way back to the wires. These units are clipped in top and bottom and you can easily see these clips. Squeeze them while pushing on the rotary numbered selector and it should break free towards the front of the car. With the CC out, I set it up right and used a Q-tip with rubbing alcohol around each of the buttons, and since it was sitting upright, some of the alcohol will run down between the buttons and dissolved the years of beverage that had spilled and stuck the buttons.
Now remove the ash tray which is held in by two screws.
Now you should be able to see the air bag module. It is held with nuts on three corners. Remove the two nearest you. The third is in the right far corner. You need to pull the right side HVAC black air vent straight out from the ‘firewall.’ It is just a slip fitting and flexible. Then you can get that nut with an extension. Don’t take that nut all the way off.
Pull the module out. You actually have a lot of wiring to work with lengthwise. Unclip it, install new/new used one. I had to grind down two tabs (one on top one, one bottom of plug) on my big yellow plug because mine was a K module and the replacement I got was a G, which is an earlier generation and has identical function, but has idiot proof plug differences. (If you have side curtain airbags, it makes a difference whether G or K – but it doesn’t matter with just the two front bags on my car)
Reinstall the airbag module, reassemble, enter radio code, go to the air bag section of VCDS Lite or VAG-COM , click recode button, type in the code taken from the old module, and enter. Clear any fault codes, and all should be good. (See final picture of it put back together)