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Old 18th September 2021, 16:12   #1
paulonsite
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Default Baffling Airbag problem

Hi All! Thanks for looking.

My airbag light came on and I had a look at the fault codes using TOAF and the AutoLiv software (cause my car has them, not the earlier ones). There were no faults on the TOAF other than 'no module' on SRS, but this forum explained why that is (need AutoLiv software not TOAF).

I got error codes 805 and 211 (wiring resistance and no signal from LH side impact sensor).

SO I purchased and fitted the correct LH side impact sensor and much better underseat connectors (SupaSeal). No joy. Changed the polarity of all the under seat cables, testing one by one, until...no joy. I am now getting another error, as follows:-

805 - front tensionor circuit - resistance too big
211 - Left side impact sensor - no signal
809 - left front airbag ignition circuit - resistance too big

I am totally baffled, and a bit fed up. I just don't get how the new (correct) LH SIS is not working. Is there anywhere else the wiring could be dodgy? In other news BOTH mechanical seat belt tensioners have lost their nuts and dangle under the seat but I couldn't see a pot or similar measuring the tension on them...or am I wrong?

Any thoughts, would be greatly appreciated. BIG thanks to the forum btw for all the info in Technical Help that has gotten me this far rather than crying into the IPK...

Best washes,

Paul.
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Old 18th September 2021, 16:41   #2
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On mine it was the connector to the side sensor, I presume it must have got damp and they was some resistance on the pins in the plug, I removed and refitted it several times to clean them and it fixed it.
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Old 18th September 2021, 17:14   #3
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Quote:
Originally Posted by paulonsite View Post
Hi All! Thanks for looking.

My airbag light came on and I had a look at the fault codes using TOAF and the AutoLiv software (cause my car has them, not the earlier ones). There were no faults on the TOAF other than 'no module' on SRS, but this forum explained why that is (need AutoLiv software not TOAF).

I got error codes 805 and 211 (wiring resistance and no signal from LH side impact sensor).

SO I purchased and fitted the correct LH side impact sensor and much better underseat connectors (SupaSeal). No joy. Changed the polarity of all the under seat cables, testing one by one, until...no joy. I am now getting another error, as follows:-

805 - front tensionor circuit - resistance too big
211 - Left side impact sensor - no signal
809 - left front airbag ignition circuit - resistance too big

I am totally baffled, and a bit fed up. I just don't get how the new (correct) LH SIS is not working. Is there anywhere else the wiring could be dodgy? In other news BOTH mechanical seat belt tensioners have lost their nuts and dangle under the seat but I couldn't see a pot or similar measuring the tension on them...or am I wrong?

Any thoughts, would be greatly appreciated. BIG thanks to the forum btw for all the info in Technical Help that has gotten me this far rather than crying into the IPK...

Best washes,

Paul.

Changed the polarity of all the under seat cables, testing one by one. Why would you want to change the polarity ?


In other news BOTH mechanical seat belt tensioners have lost their nuts and dangle under the seat but I couldn't see a pot or similar measuring the tension on them. They shouldn't be disconnected, in the event of a shunt, without them being connected they won't do their job of keeping you secure in your seat. There is no tension to be measured, why they are called that is that in the event of an rta the restraint system causes the ' tensioner ' to operate and tension, tighten, the belt sufficient to keep you safe in your seat.


As SPC says, condensation damage of plugs and pins is a favourite in this area and may be your problem, whilst you have been checking the wiring etc. you could have introduced the third fault simply by disturbing a loom which has another plug/socket with corroded terminals.
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Old 18th September 2021, 17:39   #4
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I'm chasing a SRS fault on my daughter's ZS180 at the moment, side impact sensor too which I've replaced but still got a fault, fortunately I have my own T4, which suggests I check the wiring between the connector and the SRS module (C0256/12 and C0950/2 slate wires).

Don't think you're that far from Wolverhampton are you? Arctic and others on here arrange a meet there, they usually have someone with a T4 who can diagnose your problem.

Regards
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Old 20th September 2021, 12:40   #5
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Quote:
Originally Posted by SCP440 View Post
On mine it was the connector to the side sensor, I presume it must have got damp and they was some resistance on the pins in the plug, I removed and refitted it several times to clean them and it fixed it.

Thanks - very helpful
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Old 20th September 2021, 12:42   #6
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Why would you want to change the polarity?

Sorry I shoudl have bene clearer, I was checking the polarity. The colours on my wires under the LH seat do NOT match the diagrams and photos on here, so I wanted to eliminate guess work.


In other news BOTH mechanical seat belt tensioners have lost their nuts and dangle under the seat but I couldn't see a pot or similar measuring the tension on them. They shouldn't be disconnected, in the event of a shunt, without them being connected they won't do their job of keeping you secure in your seat. There is no tension to be measured, why they are called that is that in the event of an rta the restraint system causes the ' tensioner ' to operate and tension, tighten, the belt sufficient to keep you safe in your seat.
- yes I know, I didn't remove them, the mechanic lost them when fitting a new handbrake handle



As SPC says, condensation damage of plugs and pins is a favourite in this area and may be your problem, whilst you have been checking the wiring etc. you could have introduced the third fault simply by disturbing a loom which has another plug/socket with corroded terminals.[/QUOTE]

- Any idea where? Everything looks good inside the car, including connections to the Airbag CU and the BCU.
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Old 21st September 2021, 11:15   #7
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Quote:
Originally Posted by paulonsite View Post
I got error codes 805 and 211 (wiring resistance and no signal from LH side impact sensor) ...

805 - front tensioner circuit - resistance too big
211 - Left side impact sensor - no signal
809 - left front airbag ignition circuit - resistance too big

I just don't get how the new (correct) LH SIS is not working.
Hello Paul,

The codes seem to indicate an open circuit or poor connection prior to the left hand tensioner, impact sensor and airbag.

As vitesse has suggested, why not message Arctic to see if a T4 can be made available at the next Wolverhampton meeting. The more clues you can gather the better.

Simon
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Old 21st September 2021, 11:33   #8
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Quote:
Originally Posted by SD1too View Post
Hello Paul,

The codes seem to indicate an open circuit or poor connection prior to the left hand tensioner, impact sensor and airbag.

As vitesse has suggested, why not message Arctic to see if a T4 can be made available at the next Wolverhampton meeting. The more clues you can gather the better.

Simon

Thanks Simon, I've actually got an OBD2/T4 booked with my local mechanic tomorrow. The nano is on the 3rd, my MOT is the 5th. Either way, I don't think I'm making that MOT due date...




Thanks again,


Paul.
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Old 21st September 2021, 12:46   #9
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The mechanical cables that aren't connected under the the seat aren't anything to do with the airbag they're purely there to adjust the height of the top seat belt mounting depending on the position of the seat


The seatbelt pretensioner is part of the stalk that the seatbelt clips into

Russ
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Old 21st September 2021, 15:31   #10
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Quote:
Originally Posted by paulonsite View Post
Thanks Simon, I've actually got an OBD2/T4 booked with my local mechanic tomorrow. The nano is on the 3rd, my MOT is the 5th. Either way, I don't think I'm making that MOT due date...




Thanks again,


Paul.
I'd be surprised if your local mechanic has a T4, generic OBD2 will return the same codes as toaf. Where about in Birmingham are you? I'm just north of Birmingham and have a proper T4
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