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Discussion Starter #1 (Edited)
In urgent need of advise from any "Airbag" experts as I am at a loss what to do next to switch off the airbag light.
The code reader shows two faults
1.Low battery voltage
2. warning light activated.

Tried two different code reset readers/programmes neither removed the troubled faults.and the warning light is still activated.
Anyone with any suggestions?
The car is a Phase 1 spider twinny with TRW airbag ECU
 

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Yeah,

"1.Low battery voltage"

Warnings don't happen for no reason. I'd say that you are clearing the fault record, but the fault is still being recognised as being present.

Measure the battery voltage at the airbag ECU. It should be the red wire going to pin 15. If that checks out, get your battery tested.

The second item is I think just recording that the warning light was switched on as the result of '1'.
 

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Fiat ECU Scan should be able to turn it off. Its a free app with partial features or a full app if you want to pay for it. Turning off the airbag is a free feature. I have used it to reset my airbag on my phase 2 spider. Have a quick search for the Fiat ECU Scan and have a chat to one of the guys who have a ph1 car for advice.
 

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Discussion Starter #4
Pin 15 measures 12.3v Tried to switch off the fault codes using a dedicated sykes pickavant ACR4 code reader and a commercial SOHIO all singing and dancing bit off kit borrowed of an Alfa Indie who also could not clear the codes. So whilst I can read the codes I cannot clear them out of the memory. Thanks Gt paddy and PKR ,guys keep coming up with any advice I am more than welcome to try anything out of desparation.
 

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Eliminate the silly :
Disconnect the airbag ECU from the car. Does the warning light go off? The warning light is supplied by the ignition and grounded by the ECU. If it remains on when disconnected from the ECU, there's a short in the warning light wiring somewhere.

Check the ECU ground.
Check continuity from pin 14 to the car body. Check resistance if you can.

Probably best with the ECU disconnected from the car :

Check continuity and resistance between each device pin on the ECU and related pretensioner/airbag.
Check continuity between : ( wiring and wire colour from Pre May 1997 Phase 1 )
ECU pin 6 and RH pretensioner pin 1 ( Brown wire )
ECU pin 7 and RH pretensioner pin 2 ( Brown-Black wire )
ECU pin 11 and LH pretensioner pin 1 (Green-Black wire )
ECU pin 10 and LH pretensioner pin 2 ( Green wire )
ECU pin 3 and passenger airbag pin 1 ( Yellow-Black )
ECU pin 4 and passenger airbag pin 2 ( Yellow wire )
ECU pin 1 and driver airbag pin 1 ( Blue-Black )
ECU pin 2 and driver airbag pin 2 ( Blue wire )

I'd be very careful about doing this because I wouldn't want to put any voltage across the explosive device so if you do it'd be worth downloading the workshop manual for this to ensure you're getting the pins correct and also as a sanity check look at the colour of the wire each end. Or maybe disconnect the airbags/pretensioners first.

Difficult to advise further really as I wouldn't want to take any chances with explosive devices! The manual states you should be disconnecting the airbags and pretensioners and putting loads across them ( value unknown ) before doing any diagnostics ( OK I imagine if just resetting ).

I also looked through the troubleshooting guide in the workshop manual ( volume 3 Section 55-23 ) and there's not a lot else it can suggest.
 

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Discussion Starter #6 (Edited)
Thanks PKR the light stays on when the ECU is disconnected. so you are probably on the right track with the circuit being grounded. I have tried another Binnacle and that airbag light also stayed on . So your theory on it being grounded is to be explored as it is only one wire feed from the Ecu pin 13
I have workshop manual to follow

Alfa Seltzer on another thread has advised
"This year is fine, but apparently in 2012 the function of the airbag light will be inspected, ie:it must be seen to illuminate on ignition before dimming again, simply disabling the bulb will not be an option"

If he is right a lot of members will be asking for help with this area of airbag problems
 

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That's a bit of a surprise!

OK, next you need to try and find connector G380. It's near the fusebox somewhere and has just two wires - Purple-White and Light Blue-Red. If you disconnect that and the warning light remains lit, your short is in the dashboard area. If the light goes off you need to look along the path down the driver's sill to the back seat area.

Good luck!
 
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