Airbag fault 01218

[Caino6]

Hi,

Hope everyone is keeping well in these difficult times, I’m using my time fixing all the little things that need fixing, one of them is the airbag wiring on the S4. I moved the seat back the other day and ‘ping’ airbag light come on the instrument display. 01218 passenger side airbag fault N200 stored. I unbolted passenger seat to have a look, the wiring connector on the seat and in the connector of the body harness/seat harness has already been replaced (not to a great standard). I’m going to remove the seat completely once some wiring connectors have turned up as I have had to order some more as I have run out (typical) and replace both the 2 wires completely cutting out both the poor joins that the previous owner has done, but the wiring is as follows, there are 3 wires going in to the connector from the body harness, blue, white and brown then the seat harness just has a blue and a black wire that goes to the side airbag. The blue wires were soldered together, and the white wire was soldered to the black wire. Does this ring any bells with anyone? And The brown wire was just bare floating around in the connector block under the carpet. Does this go to anything at all?

any advice would be great!

thanks

caine

[Alan02]

Hi Caine, I had to guess the model variant of your car, but looking at a 2004 onwards CFD. on elsawin, the wiring for N200 is as follows:

br: Ground wire in airbag wiring, on T3d/3 on plug. Earth connection 2 on airbag wiring harness.
bl: to T46 on airbag control module, from T3d/2 on plug.
ws: to T45 on airbag control module, from T3d/1 on plug.

N199 is similar except T3c/1 is gn coloured wire.

I hope this helps.

[Caino6]

Hi Alan

thanks for the reply, yes it’s a 2004 S4. As the connectors had all been cut out already I was just trying to figure out what’s what as I have very limited info on any Audi systems. I unbolted the drivers seat to see if that had all been cut out too, but it hasn’t, it’s all as it should be. The brown wire in the 3 pin body harness goes to nothing in the 2 pin connector in seat harness. So I take it this wire is not used?

[Alan02]

Looking at the diagram, you would only have 2 wires bl,ws at the yellow plug - going back to pins 46/45 at the Airbag module. At N200 (3 pin yellow plug) there would be a ground in position 3 of that plug which goes to (in diagram speak) : Earth connection 2, in airbag wiring harness. This earth connection is mirrored for the other N199 Igniter in other seat, so in effect they both join. Summary: 2 wires going into yellow plug @ N200........3 wires at N200 side of plug ( earth included). I hope you can understand that!

Airbag control unit shows in center tunnel under handbrake lever if you require to locate it.

[Caino6]

Hi Alan


So from what I gather from the info you have given me, the 2 wire set up is correct, and the 3rd spare brown wire that comes up to the connector through the floor does not go to anything on the seat wiring? Does the extra brown wire which was not connected to anything need to go down to a body earth? Maybe I’ll see if I can upload a picture once my connectors turn up to make it clear to see what’s going on.




I’m sorry if I sound stupid, but I’m not sure what N200 and N199 refers too lol I wish I did but it’s my 1st experience with a VAG product you see, I’m a Citroen tech by trade (unfortunately) and grew up messing around with performance Vauxhall’s (unfortunately) now at the age of 31 with 1st child on the way thought I ought to grow up a bit haha!

[Caino6]

And one more thing, I know this sounds silly, but when it says 01218 passenger side airbag, it does actually mean passenger side for a RHD vehicle doesn’t it? Only reason I ask is that Citroen Sometimes use the same terminology on their vehicle when airbag codes are present but when they put ‘passenger side’ they actually mean passenger side for LHD vehicle, which isn’t confusing at all!!

ps ignore the picture I attached was just seeing if I could actually attach images lol

[Alan02]

Yes passenger seat is on your left. Sorry, N200 is your passenger side airbag igniter, and N199 is your drivers igniter. You mention N200 in your fault code. The earth is actually connected in the harness at `312 - in airbag wiring .harness`. I`d guess if you have a Multimeter you can easily test earth to confirm it has continuity.Airbag diagram.jpgAirbag Legend.jpg
Sorry this text has gone all over after I uploaded images.

[Caino6]

That makes a bit more sense. Thanks for the diagrams, very helpful, much appreciated. Once I have my connectors I’ll take seat out and work it out from the diagram. Thank you very much!

caine

[Alan02]

You`re welcome. Let us know how you get on.

[Caino6]

Right all sorted, i found that the earth for the side airbag isn’t it the 3 pin plug with the 2 trigger wires, it’s actually it’s own 1 pin connector on the underside of the seat, it’s a thicker gauge brown wire on its own with a 1 pin connector. This connector contact pressure was poor, so I cut out the plug and hardwired, and I also cut out the connector that the previous owner had done, and hey presto all is good again!

thank you very much for all the info and the pictures of the wiring diagrams Alan, it was much appreciated!

Caine