C5 MkI 2.2HDi - Airbag faults after kerbing car

[WillyR]

Please forgive me if I am duplicating any previous posts - have just spent 1½ hours looking without success.

On Saturday I kerbed the car (stupid idiot) at about 20mph damaging the front right wheel rim. The SERVICE light illuminated on the dash, and investigation showed AIRBAG FAULT on the display screen (no dash light on this model). Like all faults, this disappears only to return every time the system cycles through the faults (door open, seatbelt, etc.)

There are no other faults or misbehaviour, as some posts have suggested would appear - indicators, horn, lights etc.

Ben82 very kindly had a look at the car with his LEXIA yesterday evening, finding the following faults:

Code P1211 - Temporary Fault - Front Left Satellite Not Defined
Code P1210 - Temporary Fault - Front Right Satellite Not Defined
Code P10D0 - Firing Test not confirmed by safety sensor Not defined
Code P10A0 - Pretensioners fired Not Defined

These codes were resettable but returned every time the car was started.

I took the car to my local Citroen garage (where I bought the car) today, and they logged the following:
First test – as we saw last evening - Code numbers not given by Citroen (must be secret!!)
Temporary Fault – Front Right Satellite Not Defined
Temporary Fault – Front Left Satellite Not Defined
Permanent Fault – Firing Test not confirmed by the safety sensor Not Defined
Permanent Fault – Pre-tensioners fired Not Defined

Second test – after clearing faults
Permanent Fault – Firing Test not confirmed by the safety sensor Not Defined
Permanent Fault – Pre-tensioners fired Not Defined
Dash SERVICE light still illuminated and AIRBAG FAULT shows on display screen.

I checked all the passenger footwell wiring yesterday, and found all 4 cables and connectors clean and in good condition, with no sign of humidity at all (first time since I bought the car that the carpets have been lifted)
I stripped the door pillar trim out and checked the seatbelt mechanisms this afternoon, and nothing seems to be amiss. Swapping the pretensioners over doesn't seem to be of any use as both are reported as fired not defined.

I desperately need to keep the car running for another three months while I wait for my new C4 Picasso (would have been a new C5 if some idiot at Citroen hadn't axed the hatch back in 2008...!!). It's sale value is only £500 (162k completed very happily over the last 11½ years).
Any help or advice in this regard will be most gratefully accepted.

[wheeler]

It kind of sounds like the pre tensioners may have fired, was there a loud bang when it happened ?
As the pre tensioners are in the inertia reels & not the stalks on the C5 its difficult to tell if they have fired.

[WillyR]

Hi. Thanks for the reply.
I didn't notice anything extra-loud (I was in emergency manoeuvre mode, and that tends to shut down unnecessary interferences like listening for loud bangs etc.) but my wife, sat in the passenger seat, says the bang - of the wheel strike and possibly the pretensioners - was VERY loud. We didn't notice any tightening of the seatbelts, and when I inspected the reels today, there was no debris or tell-tale explosive / burning smell.
I'm desperately hoping that only the pretensioners need to be replaced, but my Citroen garage tells me the ECU has to be replaced as well because it cannot recover from a firing operation. That is not something I'm looking forward to, as the airbag ECU is worth almost as much as the whole car, and including the two pretensioners AND the dreaded labour, I'm way over the value of the car.
Any thoughts on why the ECU is a mandatory replacement item after a firing?

[Stickyfinger]

Get a good one (reel) and try it BEFORE the ECU change.
Airbag ECU's are about £35squid on ebay

[WillyR]

Thanks Stickyfinger.
Seeing that I couldn't determine whether the pretensioners in my car have been fired or not, can you give me an idea how I would know whether the second hand units from EBAY are OK or not?
Next, if I do need a new ECU, is it one of those parts of the car that has to be "registered" with the main system before it will work? If YES, can a forum member with a LEXIA unit fix that?
...
Questions, questions, always questions... Thanks in advance for all responses. Enjoy the cider.

[Stickyfinger]

I woukd think a good scrap yard would be best...a local one.

All of the above I think will need a Lexia.....let us know where you are and I am sure there will be a member who can help.
Dont know, but the Lexia (should) say if the reels/airbags... have fired ??.....anybody

Just got one myself, not even installed it yet so I cant help.

enjoy Cider ?....oh no....its a blood substitute down here

[WillyR]

I've had some VERY GOOD help from Ben82, and now it is my turn to do the testing and elimination of the faults.

I was very confused when I inspected my seatbelt reels, as they showed no obvious signs (or smells) of any form of detonation be it pyrotechnic or electrical. They both leave tell-tale smells and visible evidence, but I could neither see nor smell anything untoward.

I'm in the Ashford area of Kent, if anyone within the vicinity - or anywhere else - has any ideas.

Keep taking the transfusions. They'll help, eventually...

[Ben82]

Sorry Will that I haven't got back to you about the diagrams, had a bit of a hectic evening, will have a look tomorrow... I have a train journey tomorrow, so hopefully I can get my laptop out and have a bit of a look to confirm/deny whether the 04s diagrams are the same as an 01/02.

As for breakers, Malcolm (citronut) has posted about a breakers near you a few times who seemingly often have Mk1 C5s, so you might be able to whip the ECU out of one of those (or some of the other parts).
G.M Woodgate & Son Potteries Further Quarter High Halden Ashford kent TN26 3HX Tel: 01233 850303

Really don't know if the Airbag ECU is "set up" via a Lexia or whether it needs something special before putting it in a car.

[wheeler]

When any of the devices are fired the airbag ECU is 'locked' as it records data that might need to be used after an accident to show the conditions of when they were fired. You can send them away to people to be reset by reading & re writing the EPROM inside it. If you jus,t fit the new devices the light will stay on. If you are fitting a brand new airbag ECU then you need lexia to configure it. If you are using a second hand ECU it should be plug & play as long as it has the same airbag spec, i.e. curtain airbags etc. if it has a different spec then it can be changed no problem with Lexia. The airbag ECU is not coded to a specific car so they can be swapped no problem.

[WillyR]

When any of the devices are fired the airbag ECU is 'locked' as it records data that might need to be used after an accident to show the conditions of when they were fired. You can send them away to people to be reset by reading & re writing the EPROM inside it. If you jus,t fit the new devices the light will stay on. If you are fitting a brand new airbag ECU then you need lexia to configure it. If you are using a second hand ECU it should be plug & play as long as it has the same airbag spec, i.e. curtain airbags etc. if it has a different spec then it can be changed no problem with Lexia. The airbag ECU is not coded to a specific car so they can be swapped no problem.

*******************************************
Thanks Wheeler. Understanding grows, as my learning goes.... (Edison Lighthouse circa 1968)
As you have read, above, I have (very carefully and closely) inspected my two front seatbelts and pretensioner fixings:
The reels work as they should, they roll smoothly, snatch when jerked, release, and generally work as they would out of the box - and there is absolutely no visible or nose-inspired indication that either or both of the pretensioners could have been fired - no burning / electric smell, no residue on the body of the reels or surrounding area.
*****
PLEASE SOMEONE, TELL ME THE SECRET...
IS THERE A DEFINITIVE TEST TO PROVE A PRETENSIONER HAS FIRED?
OR TO PROVE IT IS GOOD?
Can I test the device with a Fluke resistance / capacitance / inductance meter or similar device?
***
Last question tonight... To whom would I send my ECU to be reset?
***
Thanks everyone

[WillyR]

Sorry Will that I haven't got back to you about the diagrams, had a bit of a hectic evening, will have a look tomorrow... I have a train journey tomorrow, so hopefully I can get my laptop out and have a bit of a look to confirm/deny whether the 04s diagrams are the same as an 01/02.

As for breakers, Malcolm (citronut) has posted about a breakers near you a few times who seemingly often have Mk1 C5s, so you might be able to whip the ECU out of one of those (or some of the other parts).
G.M Woodgate & Son Potteries Further Quarter High Halden Ashford kent TN26 3HX Tel: 01233 850303

Really don't know if the Airbag ECU is "set up" via a Lexia or whether it needs something special before putting it in a car.

****

Cheers Ben82. When you have the time to look at the schematics for me is just fine.
I have bought bits from this guy many times, for my XM V6, Xantia 2.0HDi 110, and my C5, as he is about 6 miles from me, and you are right. Over the years he has had quite a few C5s in his yard.
Don't forget to speak to your friend about my Superchips Engine upgrade, or maybe, to point him in my direction.

[wheeler]

If you search for airbag ecu reset on ebay there are loads of peope offering the service, saw it for as low as £20.

Dont ever go poking an ohmeter into a pyrotechnic device, an ohmeter sends out a small current that can potentially detonate it.

[WillyR]

If you search for airbag ecu reset on ebay there are loads of peope offering the service, saw it for as low as £20.

Dont ever go poking an ohmeter into a pyrotechnic device, an ohmeter sends out a small current that can potentially detonate it.

***
OK, warning received. SO... How does one tell if a pretensioner has fired or not? There must be some way to check it.

[Ben82]

Cheers Ben82. When you have the time to look at the schematics for me is just fine.
I have bought bits from this guy many times, for my XM V6, Xantia 2.0HDi 110, and my C5, as he is about 6 miles from me, and you are right. Over the years he has had quite a few C5s in his yard.
Don't forget to speak to your friend about my Superchips Engine upgrade, or maybe, to point him in my direction.

Check the link with the 04 and 05 ones I sent there's a folder there now for the 01 ones... the only diagram that looks different to me is the installation one, and seems to be just a reordering of the images. (but that's only from my brief look).

[WillyR]

Thanks Ben82.

Your help is much appreciated.