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Omega Help Area => Omega Electrical and Audio Help => Topic started by: Omega VT3000 on 15 June 2009, 09:43:45

Title: Airbag fault
Post by: Omega VT3000 on 15 June 2009, 09:43:45
Hi all,

Not posted for a while as I have been snowed under. The Polac has an airbag fault with the telltale being permanently illuminated.

I borrowed a diag lead and used the "My Naff Code Reader" demo software that gives "Driver Airbag Squib High Resistance" as the fault. Look at the data, the resistance is 6.6 ohms where as the passenger side is under 2 ohms.

I assume that this is refering to the steering wheel airbag as there is also information relating to "Driver Side Airbag" which I assume are the one in the seats.

I have changed the airbag to no avail and oddly the resistance doesn't change if I completely remove the sterring wheel airbag.

The only curved ball is that I have had the light on since I had all of the interior including the dash out last year. I would have thought a trapped or severed wire would give a different.

Do any of you Omega wizards have any ideas please?
Title: Re: Airbag fault
Post by: VXL V6 on 15 June 2009, 16:39:05
Did you reset the code with the "My Naff Code Reader" after replacing the unit? Airbag/SRS systems do not put the lamp out when fixed like most engine management faults will.
Title: Re: Airbag fault
Post by: markey mark on 15 June 2009, 16:49:03
could be the squib  :-/
Title: Re: Airbag fault
Post by: TheBoy on 15 June 2009, 18:54:08
Could be contact unit.

Sadly, the SRS system i a bugger to fault find, as the bags and the ecu go into a special mode when disconnected, giving strange readings.

Unplug ecu and squib, and measure resitsance of wiring between the 2.
Title: Re: Airbag fault
Post by: Omega VT3000 on 15 June 2009, 22:30:19
Quote
Did you reset the code with the "My Naff Code Reader" after replacing the unit? Airbag/SRS systems do not put the lamp out when fixed like most engine management faults will.

Yes I did, I cleared the codes and the fault remains
Title: Re: Airbag fault
Post by: Omega VT3000 on 15 June 2009, 22:32:45
Quote
Could be contact unit.

Sadly, the SRS system i a bugger to fault find, as the bags and the ecu go into a special mode when disconnected, giving strange readings.

Unplug ecu and squib, and measure resitsance of wiring between the 2.
Thank you, I'll give that a go when I next get a chance.

I assume the term squib relates to the airbag itself and that I am working on the right circuit, i.e. the steering wheel?
Title: Re: Airbag fault
Post by: TheBoy on 16 June 2009, 19:02:34
Quote
Quote
Could be contact unit.

Sadly, the SRS system i a bugger to fault find, as the bags and the ecu go into a special mode when disconnected, giving strange readings.

Unplug ecu and squib, and measure resitsance of wiring between the 2.
Thank you, I'll give that a go when I next get a chance.

I assume the term squib relates to the airbag itself and that I am working on the right circuit, i.e. the steering wheel?
yup
Title: Re: Airbag fault
Post by: Dave DND on 16 June 2009, 19:15:09
When we remove airbags for large multimedia applications, we put a certain size resistor in place of the airbag so that the airbag ecu`s do not show a fault with the airbag removed. Never done it on an Omega, so unsure of the vaules.

In theory (and it is only that) if you knew the value of the resistor needed, you could diagnose the fault by removing a suspicious component, and replace it with the resistor and see what happens to the fault codes.

Obviously be bloody carefull playing around with airbags, and observe any discharge procedures before disconnecting them.
Title: Re: Airbag fault
Post by: Marks DTM Calib on 17 June 2009, 08:11:27
4 ohms....

Anyway, its the squib thats the likely cause.

Sometimes its little more than the connectors needing a good clean.
Title: Re: Airbag fault
Post by: Simon_Omega on 17 June 2009, 13:32:44
i fitted leather before, and have to tech 2 it to reset or similar.
Title: Re: Airbag fault
Post by: TheBoy on 17 June 2009, 18:31:48
Quote
4 ohms....

Anyway, its the squib thats the likely cause.

Sometimes its little more than the connectors needing a good clean.
when measured with tech2. iirc, weird results measuring with a meter...