[Warning Light] Airbag warning light

[andrewmcleod]

OK, so this is my girlfriend's 2008 Berlingo Multispace (the newer version). It has a both airbag warning lights displaying (for the passenger airbag light as well?) and gives a beep and warning 'airbag/seatbelt faulty' (or something like that) at start-up. It does appear to have a passenger airbag (at least it has a bit on the dashboard that says 'airbag' on the passenger side and it has the deactivation switch).

We took it to the garage and (after £30 for the privilege) it was determined to be an 'airbag ECU fault'.

I've plugged and unplugged all the connectors under the driver's seat, and sprayed the contacts with contact cleaner. There don't appear to be any wires of any sort under the passenger seat; I'm not sure if it has pretensioners.

I bought a second-hand airbag ECU off eBay with a matching model number (9665250180, taken from an 09 Partner based on what's written on it in marker pen) and (after the turning everything off, waiting ten minutes, disconnecting the battery, waiting 30 minutes faff) replaced the original airbag ECU with the 'new' unit (spraying all the contacts with contact cleaner again...).

Turning it all back on again gave a single airbag light - which is at least different? I don't know if this is because the 'new' unit needs to be coded to the car, or if it's been taken from a crashed vehicle, or what. Since this didn't fix the problem, I repeated everything and put the original unit back in.

I don't know how relevant this is, but the car has previously had issues with the horn (airbag earthing?).

So what would you recommend next?
Buy a Lexia code reader thing and set up Diagbox etc to get some codes (est. £65 or so)? Presumably this wouldn't help you clear crash data off the airbag ECU or clone one unit to another (if this is required) etc. and will probably end up just indicating there's a wiring fault or something...
Go looking for the fault elsewhere? I have a reasonable multimeter but no wiring diagrams/car electrical experience. I have previously replaced the indicator stalks on my Yaris so have removed the airbag on that before if that's a good place to look.
Give up and send it to the garage for probably high costs?

The aim is to sell the car soonish and I think that will be very difficult with an airbag fault.

Thanks in advance - I did have a search through the forum but knowing how these things work someone will have posted the exact same question yesterday or something

[Sol]

You could have a broken clockspring ribbon in the steering wheel / com2000 unit for example or a bad SRS firing unit. You can't swap the airbag ECU as it needs coded to your VIN.

Can't help much further, this could be painful to find and repair.

I'll try to pull up the schematics tomorrow on ServiceBox when I get a chance at work, but this could drag on so that's as much help as we can give on a forum. You may be best to get Diagbox. It's not straightforward to install and use but there are plenty of videos on YouTube.

[Abaddon]

Have the same issue, but have not attempted any fixes as yet. Are those first steps all the correct ones to attempt a fix?

[Multispacer]

Don't know how much use it might be as my Airbag fault was on the previous generation M59 variant that I used to own and that turned out to be an open circuit wire.

The whole thread is here: https://www.berlingoforum.com/thread-11787.html

if you want to read through it. AS has been stated in the other answers, you really need to have a proper diagnostic carried out to get some codes that at least then point you in the right direction. Back when I had this fault I paid about £30 for the check at an independent Citroen specialist but I suspect it is more like £50+ nowadays.

[Sol]

Here are the schematics and the key to the item numbers. Plugs are shown like 5V NR which means 5 pin Black (NR = Noir) - all abbreviations are in French.

[andrewmcleod]

So the update:

Thanks to Sol for the wiring diagram etc. I spent most of a morning testing the wiring, after which I eventually confirmed to the best of my abilities that it probably really was the airbag ECU. Took it to another garage which said that it might not be worth it/would cost many, many hundreds of pounds and better to take it out and send it off myself if I could etc. I found an ECU place online that quoted an estimated repair cost of £225 - £325 + VAT for these ECUs, and was going to send it off when I checked the reviews and found they were pretty awful...

Finally, found this:
https://ecuconnection.co.uk/product/citr...er-cloning

Figured it was worth a shot. After VAT and delivery, around £100 for cloning service from old ECU to eBay ECU. At this point, we are hoping: 1) it is a fault in the airbag ECU, 2) the eBay ECU actually works...

Took about 2 weeks ish to come back, plugged the eBay unit in today.

No more lights

So about £27 for the ECU, £30 when a garage charged us for the diagnostic, and £100 for the cloning. Could have been much worse...

We bought a new XL Combo Life back in July because the old Berlingo had this airbag light problem and some suspension issues (and we were about to drive to Austria and back). Since then it's just been sitting around, meaning the delay while the unit gets reprogrammed was not a problem. Now it can go for MOT and probable suspension work and then sale

[Multispacer]

So the update:

Thanks to Sol for the wiring diagram etc. I spent most of a morning testing the wiring, after which I eventually confirmed to the best of my abilities that it probably really was the airbag ECU. Took it to another garage which said that it might not be worth it/would cost many, many hundreds of pounds and better to take it out and send it off myself if I could etc. I found an ECU place online that quoted an estimated repair cost of £225 - £325 + VAT for these ECUs, and was going to send it off when I checked the reviews and found they were pretty awful...

Finally, found this:
https://ecuconnection.co.uk/product/citr...er-cloning

Figured it was worth a shot. After VAT and delivery, around £100 for cloning service from old ECU to eBay ECU. At this point, we are hoping: 1) it is a fault in the airbag ECU, 2) the eBay ECU actually works...

Took about 2 weeks ish to come back, plugged the eBay unit in today.

No more lights

So about £27 for the ECU, £30 when a garage charged us for the diagnostic, and £100 for the cloning. Could have been much worse...

We bought a new XL Combo Life back in July because the old Berlingo had this airbag light problem and some suspension issues (and we were about to drive to Austria and back). Since then it's just been sitting around, meaning the delay while the unit gets reprogrammed was not a problem. Now it can go for MOT and probable suspension work and then sale

Good to see you've got the issue fixed. I'm assuming the Berlingo in question is a 1.6Hdi? When you do put it up for sale, make sure that you point out that as a 2008 Hdi version it has neither a DPF or any adblue/eolys additive system, as for anyone outside of the ULEZ zones it is a plus as it means the engine side is less likely to have problems

[Abaddon]

I am surely missing something here, but is it possible to buy a second hand steering wheel to resolve this issue?