Airbag lamp (Aussie in distress)

maxi_crawf · 28th February 2007, 09:26

Dear all,
I have been in contact with one of our aussie cousins and he has the old airbag lamp on, problem!, I have suggested the fix concerning the connector blocks under the front seats, but,aparrently this isnt working! his electrician seems to think its something to do with the rear seat pre-tensioners

and the fact that the resistance readings are different on each pre-tensioner, I have told that I think this is a red herring,has anyone any definitive answer to this one? I understand that the car is due for its 'Compulsory roadworthy test', MOT, I assume, and will fail on this.

He has asked questions in 'another place' any information I am happy to foreward on or you can PM him in 'the other place' as lee luck.

Regards maxi-crawf

CFS75 · 28th February 2007, 10:46

I had a similar problem with the airbag warning light last year and eventually had to take the car into the local XPart garage because all the suggested 'cures' had failed! Diag tests with T4 found a fault code relating to the rear right pretensioner. After removing the rear seats a poor wiring earth was located and repaired.
This cured the existing problem.

Kandyman · 28th February 2007, 11:03

You learn something new everyday, Thanks for the info CFS75

Can you describe a bit more what to look for under the seat if you know?

Thanks

CFS75 · 28th February 2007, 11:34

Sorry but I didn't see the actual fault. I can only quote from the invoice
"...removed rear seats and parcel shelf etc - traced wiring using wiring diagrams - found poor earth on wiring - repaired wiring - rebuild car - carry out extensive testing - no faults found at time of test."
This work cured the problem. Previously I had spent many hours fiddling about with the wiring and connectors under the front seats without success.
The Xpart garage, a Citroen dealer, said that the airbag warning light problem was also common to some Citroen models.

r44712 · 28th February 2007, 12:55

Quote:

Originally Posted by CFS75

I had a similar problem with the airbag warning light....diag tests with T4 found a fault code relating to the rear right pretensioner.

Rear pretensioners, am I missing something here?

Rich · 28th February 2007, 13:05

I was wondering that, aren't the rears just bolted to the floor pan?

CFS75 · 28th February 2007, 13:53

I've just been reading through my R75 handbook on the subject of pretensioners and there is no specific mention of rear pretentioners.

However in the Haynes Manual, Section 11.24 Seat belt components, it explains the function of front seat belt tensioners and then para 6 states;
"The rear belt inertia reels have a similar system, except that the gas canister acts directly on the belt reel via a rack and pinion mechanism. The belt can be retracted by up to 180mm when the tensioner is triggered."

Perhaps someone could clarify this query about the existence of the rear pretensioners?

JohnDotCom · 28th February 2007, 15:15

You lost me about 5 posts ago!
Seriously though, I thought only the front Belts had the Pretensioners.

Departed · 1st March 2007, 06:55

In another thread I said that it was unwise to measure the resistance of any firing components. I still wouldn't measure one!

However, maybe there is another way.

If the electrician is sure that the resistances are different, and that means one is wrong, then substituting resistors should show what is right.

The method would be to obtain two resistors, the equivalent of each of the two measured values. Then substitute one at a time so that the car has two of the same value (ie one pretensioner one side, one resistor the other side).

From memory, other systems I've seen expect around 2 ohms, but this one may be different.

28th February 2007, 09:26	#1
maxi_crawf Posted a thing or two R75 Saloon Conn CDT SE, MG ZT190+ Join Date: Nov 2006 Location: Kingston-upon-Hull Posts: 1,960 Thanks: 823 Thanked 426 Times in 274 Posts	Airbag lamp (Aussie in distress) Dear all, I have been in contact with one of our aussie cousins and he has the old airbag lamp on, problem!, I have suggested the fix concerning the connector blocks under the front seats, but,aparrently this isnt working! his electrician seems to think its something to do with the rear seat pre-tensioners and the fact that the resistance readings are different on each pre-tensioner, I have told that I think this is a red herring,has anyone any definitive answer to this one? I understand that the car is due for its 'Compulsory roadworthy test', MOT, I assume, and will fail on this. He has asked questions in 'another place' any information I am happy to foreward on or you can PM him in 'the other place' as lee luck. Regards maxi-crawf Last edited by maxi_crawf; 1st March 2007 at 08:29..

28th February 2007, 13:05	#6
Rich Posted a thing or two http://Roadca.ms - Letting you see what they see! Join Date: Nov 2006 Location: Yup Posts: 1,786 Thanks: 0 Thanked 7 Times in 1 Post	I was wondering that, aren't the rears just bolted to the floor pan? __________________ https://VehicleGPS.UK http://www.MotorwayCameras.co.uk

28th February 2007, 10:46	#2
CFS75 Loves to post Rover 75 2.5 V6 Connoisseur SE Auto Join Date: Nov 2006 Location: Colchester Posts: 341 Thanks: 7 Thanked 3 Times in 3 Posts	I had a similar problem with the airbag warning light last year and eventually had to take the car into the local XPart garage because all the suggested 'cures' had failed! Diag tests with T4 found a fault code relating to the rear right pretensioner. After removing the rear seats a poor wiring earth was located and repaired. This cured the existing problem.

28th February 2007, 11:03	#3
Kandyman Banned ROVER 75 2.5 V6 Connoisseur SE Limousine 2004 Join Date: Oct 2006 Location: Welling Posts: 10,995 Thanks: 0 Thanked 2 Times in 2 Posts	You learn something new everyday, Thanks for the info CFS75 Can you describe a bit more what to look for under the seat if you know? Thanks

28th February 2007, 11:34	#4
CFS75 Loves to post Rover 75 2.5 V6 Connoisseur SE Auto Join Date: Nov 2006 Location: Colchester Posts: 341 Thanks: 7 Thanked 3 Times in 3 Posts	Sorry but I didn't see the actual fault. I can only quote from the invoice "...removed rear seats and parcel shelf etc - traced wiring using wiring diagrams - found poor earth on wiring - repaired wiring - rebuild car - carry out extensive testing - no faults found at time of test." This work cured the problem. Previously I had spent many hours fiddling about with the wiring and connectors under the front seats without success. The Xpart garage, a Citroen dealer, said that the airbag warning light problem was also common to some Citroen models.

28th February 2007, 13:53	#7
CFS75 Loves to post Rover 75 2.5 V6 Connoisseur SE Auto Join Date: Nov 2006 Location: Colchester Posts: 341 Thanks: 7 Thanked 3 Times in 3 Posts	I've just been reading through my R75 handbook on the subject of pretensioners and there is no specific mention of rear pretentioners. However in the Haynes Manual, Section 11.24 Seat belt components, it explains the function of front seat belt tensioners and then para 6 states; "The rear belt inertia reels have a similar system, except that the gas canister acts directly on the belt reel via a rack and pinion mechanism. The belt can be retracted by up to 180mm when the tensioner is triggered." Perhaps someone could clarify this query about the existence of the rear pretensioners?

28th February 2007, 15:15	#8
JohnDotCom * Rover 75 FaceLift Tourer CDTi 170BHP Auto ConnSE 2005 Model Starlight Silver Join Date: Nov 2006 Location: Abergele Posts: 28,735 Thanks: 0 Thanked 6 Times in 5 Posts	You lost me about 5 posts ago! Seriously though, I thought only the front Belts had the Pretensioners.

1st March 2007, 06:55	#9
Departed Retired -- Join Date: Jan 2007 Location: -- Posts: 3,785 Thanks: 0 Thanked 4 Times in 4 Posts	In another thread I said that it was unwise to measure the resistance of any firing components. I still wouldn't measure one! However, maybe there is another way. If the electrician is sure that the resistances are different, and that means one is wrong, then substituting resistors should show what is right. The method would be to obtain two resistors, the equivalent of each of the two measured values. Then substitute one at a time so that the car has two of the same value (ie one pretensioner one side, one resistor the other side). From memory, other systems I've seen expect around 2 ohms, but this one may be different.