Airbag fault light on.
 

Hi guys. Hope everyone is well . After having fixed my ABS light fault with the help of you guys, My airbag light is on and not for going off. I've tried the usual method of checking the connections under the seats. I've removed the connectors and just soldered the wires together. No joy light still on. I've checked under the carpets for water ingress but both sides are dry and visually the side impact sensors look ok. I've removed the steering wheel to look at the airbag connection but again it looks ok. I know they could have a fault. I've now removed the airbag ECU next to the handbrake. again its all dry and looks okay. So Now I've bought a second hand airbag ECU from Ebay and waiting for it to arrive. Does anyone Know if I have to get it set up at a garage or can I just plug it straight in. I'm stuck with the light on and the MOT is due in 2 weeks. Any advice would be welcome.

Many thanks. Alex.

Do you have any info about the replacement ECU? If the donor car was involved in an accident that triggered the airbags then the ECU is a paperweight, cannot be reused. Also not all airbag ECUs are the same, the donor car must have the exact same number of airbags as yours. If the donor car had additional airbags ("A" pillar airbags?) the ECU will log a fault because it can't speak to the missing airbags.

Provided the ECU is good and from the same spec of car it "shouldn't" require the involvement of a T4.

Under no circumstances connect the new ECU without bolting it in position first or it will log an accident rendering it useless.

Hi Alexander.
I feel your pain, as i am too going through the same process, light came on did the unplug the under seat connectors, clean and plug back in no joy.

removed the connectors and joined them with some other connectors again no joy, so decided to connector wire direct, no joy, changed out the pretensioner for another one no joy.

Removed the side impact sensor changed it out still light is on.

T4 is telling me its right side.
https://i.imgur.com/jveYNOOl.jpg1

https://i.imgur.com/PolHZEll.jpg2

https://i.imgur.com/gKT7Nrjl.jpg3

https://i.imgur.com/WQjYEAil.jpg4

https://i.imgur.com/aE3YGrDl.jpg5

Even with all that info i am still chasing the problem, tomorrow is another day and hopefully i will get somewhere.

PS also check you SRS fuse behind the glove box.

Steve, your problem sounds similar to one I was chasing on my daughter’s ZS180 (using my T4) it insisted that my left impact sensor was defective so I bought another one. No better, and still T4 insisted it was the left sensor. So I swopped the right and left sensors expecting the fault to move to the right side. It didn’t, no error anymore and airbag light out - I’ve yet to understand that one!
So try changing sensors left to right and see what happens.

Good luck

steve. the last paragraph on your post. does this mean that the ECU needs to be earthed before connection ? is this the reason why it will wall itself .. ?

ABS Fault
 

Hi, forgot to mention that I changed the fuse even though the original one looked ok. The new/old airbag ECU has the same number. All it said it was from a 2002 Rover 75, it wasn't too expensive so not the end of the world. The only thing I can think of is that about a day or 2 before the light came on is that a bolt detached from the drivers seat, it is the small 10mm bolt that seems to hold the back of the seat together with the base, it has a small plastic collar that the bolt sits in. Hope I'm explaining this okay. Anyway it pushed the back away from the base on the o/s of the driver seat. Now I've noticed that there's a wire going up the back of the seat on that side. Can anyone tell me what that wire is for and is it possible that it's got stretched when the back of the seat came loose on that side? Sorry for the long winded story. I'm just a novice with a tool box. I'm the same height as Edd China but that's where the similarities end.

Thanks in advance. Alex.

I'm quoting Russ (BigRuss) from a thread about replacing blown airbags:

"Do not under any circumstances plug in the replacement ecu without bolting it down first.
If you do it will render the ecu useless as it will log crash data and you will be back to square one."

Yes, the small black earth wire witha ring connector on the end must be bolted down before power is applied to the ecu.

If the other car had the exact same airbag setup then it shouldn't log a fault. Best bet is to fit the new airbag ecu, then get the car reconfigured on a T4, this will update the config in the replaced ECU.

thankyou andy. its good to know this. all is clear now !!!