Peugeot 207 Airbag faults (open circuit, coherence fault)

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111CH1EF111
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Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by 111CH1EF111 »

Peugeot 207 2006 1.6 HDi
Seatbelt/airbag fault on dash

I ran Peugeot Planet on the car and it came back with an "Front right side air bag fault. open circuit . Local" open circuit to the Drivers side seat airbag, after messing with the connectors and then removing them and soldiering the wires directly together as the fault was intermittent, I found actually wires were broken as at the back of the seat, and so I soldered them back together.

Now, I have 2 faults come up;
Front right side airbag fault . Coherence fault . Local .
Steering column air bag fault . open circuit . Local .

I then changed the comms unit and it made no difference. What can it be?

I have thought, the steering wheel and seat airbag are not bolted in while I test them (do them need that as an earth?)
I am almost certain I have not wired the seat connector wrongly when taking the connector out, but maybe I did?)

Any help would be much appreciated, thanks.

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white exec
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by white exec »

I think you'll have to take a careful and methodical check-out of the connections and wiring.
Coherence checks carried out by the ECUs are looking for correct resistance values for components, as well as continuity.
Be very careful making continuity checks on airbag circuits, as accidental triggering is a possbility.

111CH1EF111
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by 111CH1EF111 »

Thanks, I have re done the wiring and tested it and it is all correct now. So my only fault is "Steering column air bag fault . open circuit . Local ."

What is the steering column air bag ?

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GiveMeABreak
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by GiveMeABreak »

111CH1EF111 wrote:
21 Aug 2019, 08:09
Thanks, I have re done the wiring and tested it and it is all correct now. So my only fault is "Steering column air bag fault . open circuit . Local ."

What is the steering column air bag ?
It's not the driver's airbag - that is contained in the steering wheel. The one being referred to is the driver's knee airbag in the steering column as fitted to the 207 on some trim levels.
knee 1.PNG
knee 2.PNG
If fitted, this is where it is located behind this panelOnce the trim is removed, this is the module
on the underside.

111CH1EF111
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by 111CH1EF111 »

ah, that is great information, thanks. But then it throws the confusion of the fact I dont have an airbag there and the car never has had one! Any ideas?

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GiveMeABreak
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by GiveMeABreak »

You need to pop up your VIN so I can check some other information. I suspect that the Airbag ECU is not happy about your wiring - and may be giving conflicting information

111CH1EF111
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by 111CH1EF111 »

Strangely, I went through everything again, and changed nothing as far as I was aware. I redid Peugeot Planet and made the steering column airbag as showing as absent again, and then it no has got rid of the fault (fingers crossed, but it drove fine for an hour). Thanks for all your help

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GiveMeABreak
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Re: Peugeot 207 Airbag faults (open circuit, coherence fault)

Post by GiveMeABreak »

It should be absent - if you don't have it installed and the ECU is configured incorrectly it will throw the system out.