xsara picasso 2006 airbag light

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Glennh
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Joined: 22 Jul 2020, 16:55

xsara picasso 2006 airbag light

Post by Glennh »

Hello
My name's Glenn and I have had the above vehicle for 7yrs. It's the 1.6 16v and has been very reliable.
The drivers airbag light had been on for some time so with my shielding time off i decided to investigate.
I bought the laser airbag test resistor set and took the one and only plug off the comms unit and popped in the pins. Turned the ignition on and the airbag light went out and stayed out.
Pulled the resistor test tool out and the light came back on. This as I understand it means everything from this plug back to the ecu is ok.
I then took the airbag off the steering wheel and disconnected the plug for the airbag.
I then did a continuity test from the airbag plug pins back to the two pins on the comms unit , from where I had previously removed the plug for the resistor test.
I've got continuity on both. This means it must be the airbag as I understand it.
So bought a new airbag £40 and fitted it but still have the light on.
Code is p1801 ignitor circuit open level 1 etc.
Can anyone put me straight?

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GiveMeABreak
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Re: xsara picasso 2006 airbag light

Post by GiveMeABreak »

It'll very likely be your clockspring wiring in the comms unit. As the wheel is turned constantly over the years back and forth, the flat cable wiring suffers internally within the ribbon.

Glennh
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Re: xsara picasso 2006 airbag light

Post by Glennh »

I thought the continuity test between the comms and the airbag plug ruled that out

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GiveMeABreak
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Re: xsara picasso 2006 airbag light

Post by GiveMeABreak »

Have a squiz at this video - you can see that the issue was with the comms unit in this case, but he uses an airbag tester like you describe.


wheeler
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Re: xsara picasso 2006 airbag light

Post by wheeler »

I donk know if you are aware but most of the plugs on the airbag system are designed so that the terminals short together when the plug is disconnected (to stop any static buildup I believe). This means if there is a break in one of the wires you may actually be measuring both of them & it can show good continuity when there is nothing plugged into it.
Try plugging the dummy back in & turn the steering lock to lock & see if the light comes back on.

Glennh
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Re: xsara picasso 2006 airbag light

Post by Glennh »

Give meABreak
This was the tutorial I followed.
Wheeler
I'm aware the pins in the airbag itself short out but not any others

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Paul-R
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Re: xsara picasso 2006 airbag light

Post by Paul-R »

When I replaced the passenger seat side airbag in my 2003 C5 I also replaced the ECU as I was given to understand that once it has logged a blown bag it needs to be virginised as it can't be cleared with a Lexia. Is this a possibility here?

Glennh
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Joined: 22 Jul 2020, 16:55

Re: xsara picasso 2006 airbag light

Post by Glennh »

Tried continuity with the blue comms plug in and still tests ok. Only get continuity 1 pin to 1 pin not via either.
Put the airbag tool in ,turned on the engine, turned the wheel lock to lock ,no airbag light on.

Paul-r
In my ownership no airbag has deployed.

Glennh
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Joined: 22 Jul 2020, 16:55

Re: xsara picasso 2006 airbag light

Post by Glennh »

Could it be a case of it has continuity but the resistance through the wiring is incorrect?

Glennh
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Re: xsara picasso 2006 airbag light

Post by Glennh »

Now I'm more confused.
Tried the airbag resistor in the airbag plug and the light goes off yet still comes on if I plug a brand new airbag in.

Glennh
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Re: xsara picasso 2006 airbag light

Post by Glennh »

I'm going to try swapping the plugs over with the green one that's not used . See if it connects better.

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NewcastleFalcon
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Re: xsara picasso 2006 airbag light

Post by NewcastleFalcon »

Glennh wrote:
26 Jul 2020, 08:38
I'm going to try swapping the plugs over with the green one that's not used . See if it connects better.
Keep going Glenn resolution of Airbag light on problems will be a huge benefit to others. Its not rust and mechanical failure that is going to write off perfectly good cars as uneconomical to repair, it will be stuff like airbag lights.

Yes and that small little tin of electronics the airbag ecu, which unless you have spilt several cups of coffee on it, does sit in a reasonably favourable environment for such things. Surely the enormously expensive fix of replacing an airbag ecu doesn't apply in the vast majority of airbag light on scenarios. Yes there are ones out of scrapyards, but if its anything like the Micra there are different spec Airbag Ecu's depending on model and the chance of stumbling across a match are small.

So good luck keep at it and hopefully the thread will end with a resolution.

REgards Neil

Glennh
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Re: xsara picasso 2006 airbag light

Post by Glennh »

I ended up replacing the whole comms,indicator,headlight stalks unit for a s/hand one and all is good.
My local scrappy wanted £140 but Cit-ren at Brooke wanted £40 .
I'm going to take the old unit apartand have a look as it had continuity but still didn't work properly.

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NewcastleFalcon
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Re: xsara picasso 2006 airbag light

Post by NewcastleFalcon »

Excellent news Glenn well done.

Don't think I have come ascross Cit-Ren getting a name check on here before but they do claim to be the The UK’s Number 1 French Spares Supplier so worth a link

http://www.cit-ren.co.uk/contact-us

Regards Neil