Airbag question

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moizeau
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Airbag question

Post by moizeau »

I'm sure this has been covered a million times but can I make it a million and one?
Just before the lockdown a mate dropped his Xant round for me to play with. I've had a chance today. VIN VF7**************[VIN obfuscated, can be read by forum staff] . It's a LHD with an airbag fault. Lexia has given me the following:

SAC AFK gave
Perm Fault Seatbelt trigger 2 open circuit
Perm Fault Airbag warning lamp short circuit to -ve or open circuit

SAC AFK D gave
Perm Fault Indicator lamp activation control
Perm Fault Airbag cartridge open circuit

SAC AFK G gave
Fault not referenced in after sales
Airbag cartridge open circuit

It's also got the usual pre / post heat code, i'd be disappointed if it hadn't.

I've read about the wires under the seat but no real idea which ones, where they are and how you test them. I also remember something about the deactivation key operated switch. Regarding the switch I can get Lexia to change the condition from perm to temp in the fault list depending on it's position so I'm guessing this is working?

If anyone out there recognises these faults and knows which way I should go that would be much appreciated.
Cheers

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xantia_v6
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Re: Airbag question

Post by xantia_v6 »

In general, the connectors related to the airbag system are coloured orange, so if you look under the seats for corange connectors, you should find them...
Last edited by xantia_v6 on 05 Apr 2020, 21:17, edited 1 time in total.
Reason: spelling

moizeau
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Re: Airbag question

Post by moizeau »

Thanks, I'll look for the corange ones, sorry orange.
Thanks

moizeau
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Re: Airbag question

Post by moizeau »

Someone has been here before. The plugs under the seats have been cut and the wires spliced. The issue now is...I have no idea which wires should have been connected to which? It could be a bad splice or a wrongly spliced initial repair? Any ideas on wire colours and their corresponding other halves and how I test them. I'll do a continuity test on the splices with a couple of pins.
Cheers

wheeler
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Re: Airbag question

Post by wheeler »

Don’t ever use an ohmeter on an airbag circuit, an ohmeter outputs a small current to work which could be enough to deploy the airbag if your unlucky.
Best thing to do is cut out the splices one at a time so as not to get them mixed up & redo them.
It goes without saying disconnect the battery for at least 10 minutes before working on the system.

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ksanturion10
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Re: Airbag question

Post by ksanturion10 »

Don't do continuity tests with cables connected either to the air bags or to the pyro-tensioners! - wheeler was first :)
Disconnect both end connectors and then do the test.
50% chance it could be the airbag switch into the steering wheel.

moizeau
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Re: Airbag question

Post by moizeau »

Thanks to both of you. I didn't realise an ohmmeter could do that, even with the battery disconnected.
Ksanturion, I can't disconnect the connectors, so I'll strip back the insulation on the previous splice and do a visual / pull test. Could you elaborate on the steering wheel switch please?

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ksanturion10
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Re: Airbag question

Post by ksanturion10 »

It is a coiled ribbon cable for transmitting the current to the airbag - God forbid ;).
It has to be mounted in predetermined position or it goes "bye Felicia" :D
The cable gets disconnected either, because of wrong mounting, or from too much bending cycles, or both.
When you remove the driver's airbag you will see it behind.

moizeau
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Re: Airbag question

Post by moizeau »

Thanks, I'll leave that then for the moment and check the wires under the seats.