airbag problem a4

[ruskie86]

I own a 2003 audi a4 quattro im having trouble with front passenger airbag code is sporadic open circuit pass side crash sensor g284.Ive changed it with drivers side and it stays the same .I read somewhere to check wiring between g284 and airbag control unit .Please could anyone suggest where to start thanks steve

[GeorgeE]

Bear in mind there is more than one crash sensor on the passenger side. I guess you have checked the one by the radiator, try checking the one at the bottom of the B pillar - a few people (me included) have found that water has got in there and caused corrosion. The water gets there when it builds up above a certain level in the rear door shuts.

[ruskie86]

Ok thank you georgeE ill check it out thanks steve

[Cliveski]

Last year I replaced this sensor on my 2002 A4 1.9 TDI (http://www.amazon.co.uk/-/dp/B00DTU2I2Q) with a used one off eBay (http://www.ebay.co.uk/) costing £15 delivered.

I did my research and found this was a common fault and could be replaced once the battery was disconnected. After replacement my airbag light went off without the need of a diagnostic tool.

My sensor part number was 8E0 959 643 without any letter on the end. The significance of not having the letter on the end seemed to be that it meant the sensor had two bolt holes with threads for the fixing bolts to screw into and furthermore the bolt holes were flush with the plastic casing not proud like they were on sensors with the same part number but with a letter on the end.

The reason my sensor failed was becuase the door carrier seals had perished allowing water to enter the cabin via the door sill - soaking into the foam upon which the sensor sat - the water had then corroded the sensor - even my used replacement sensor showed signs of some water damage

[GeorgeE]

There is a time and a place for secondhand, water damage items of unknown origin off ebay. I would say that a component which controls explosives packed around you in a car, designed to control a system that may save your life when it all goes pear shaped is not one of those times. I know genuine new parts seem expensive but this is one of those times where I bit the bullet and went to the dealer (well, OK TPS but same difference).

[Cliveski]

I hear what you say GeorgeE - thankfully the airbag system shuts down and won't deploy any of the airbags if the system detects a problem (as indicated by the airbag light appearing on the dash) so I would have known had the replacement sensor not worked. I do remember when researching before swapping mine that there are some sensors in the airbag system that should be left well alone as there was a risk of explosion or a permamanent airbag fault being logged.
Alas I sold the car before the airbags reached their expiry date and all needed replacing ;)