Air bag fault / warning

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

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Wul
1.8 8v
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Joined: Fri Jan 10, 2020 11:47 am
Location: Bandung, Indonesia

Re: Air bag fault / warning

Post by Wul »

dirtydirtydiesel wrote: Sun Oct 11, 2020 10:17 pm Thanks for the offer frog,

Re - the vist you, the car's not legal due to the MOT expiring last December 2019 :roll:
I can't get it through an MOT with this airbag problem.

But I ain't giving up yet :wink:
When looking at this wiring diagram from Autodata, it seems that Data Link Connector (OBD) is connecting to the airbag module through the BSI. Since you had tried to replace the airbag module and PP2000 still can't communicate to it, maybe the problem lies within the BSI.

Image

Image
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4HX Airbag 1.png
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4HX Airbag 2.png
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2001 406 D9 2.0i 16V 135 - planning to use it for at least 6 more years
1998 306 N3 1.8i 8V 103 - has been asleep for 8 years now
Wul
1.8 8v
Posts: 49
Joined: Fri Jan 10, 2020 11:47 am
Location: Bandung, Indonesia

Re: Air bag fault / warning

Post by Wul »

Sorry since I can't edit my post again, it seems A11-I in that diagram refers to the module in the engine bay (I think it's called BM34? I'm not too familiar with full mux system) instead of BSI under the steering column.
2001 406 D9 2.0i 16V 135 - planning to use it for at least 6 more years
1998 306 N3 1.8i 8V 103 - has been asleep for 8 years now
Wul
1.8 8v
Posts: 49
Joined: Fri Jan 10, 2020 11:47 am
Location: Bandung, Indonesia

Re: Air bag fault / warning

Post by Wul »

Well, it seems my first post is the correct one. Airbag module connect to BSI under the steering column. :mrgreen:

Sorry for triple posting :oops:

Image
2001 406 D9 2.0i 16V 135 - planning to use it for at least 6 more years
1998 306 N3 1.8i 8V 103 - has been asleep for 8 years now
dirtydirtydiesel
3.0 24v
Posts: 1521
Joined: Sun Apr 28, 2013 11:02 pm
Location: Coalville, Leics.

Re: Air bag fault / warning

Post by dirtydirtydiesel »

Hey
Thanks for the advice Wul.
We have tried a cloned BSi with no luck, I'm not paying out for a new one.
I plan on having a proper look at this when the day's get longer.
2002 110 HDi estate, Rapier in monaco blue! ( found quite a bit more power :cheesy: ) SOLD I've sorted the airbag light :cheesy:
1998 3.0 V6 SE coupe in Diablo Red ( my baby ) sold
2006 206 1.4 16v sport in Aegean blue ( wife's shopping trolley :roll: )

2006 BMW e61 535d m-sport :supafrisk: run's for cover :lol:
dirtydirtydiesel
3.0 24v
Posts: 1521
Joined: Sun Apr 28, 2013 11:02 pm
Location: Coalville, Leics.

Re: Air bag fault / warning

Post by dirtydirtydiesel »

Doggy wrote: Sun Oct 11, 2020 6:27 pm http://www.petrila.net/repair/index.htm

Usually works for me. Has a full-mux diagrams with wire numbers etc.

(You want section 60 "Protections, Openings etc.")
Hi Doggy,

Hope you're well?

The link you put above, if I open it I can't understand it.
Do you know how to get it in English?

Cheers DDD.
2002 110 HDi estate, Rapier in monaco blue! ( found quite a bit more power :cheesy: ) SOLD I've sorted the airbag light :cheesy:
1998 3.0 V6 SE coupe in Diablo Red ( my baby ) sold
2006 206 1.4 16v sport in Aegean blue ( wife's shopping trolley :roll: )

2006 BMW e61 535d m-sport :supafrisk: run's for cover :lol:
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Doggy
Mod with a 2.2 HDi, De-Fapped!
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Re: Air bag fault / warning

Post by Doggy »

Hi DDD, I'm fine thanks hope you are too.

Unfortunately that link hasn't worked for a year or two and I haven't found a replacement. :(
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
dirtydirtydiesel
3.0 24v
Posts: 1521
Joined: Sun Apr 28, 2013 11:02 pm
Location: Coalville, Leics.

Re: Air bag fault / warning

Post by dirtydirtydiesel »

Thanks anyway Doggy, worth an ask :roll:

Yeah I'm good thanks except for the obvious :frown:

I'll keep trying for now, thanks for the quick reply :)
2002 110 HDi estate, Rapier in monaco blue! ( found quite a bit more power :cheesy: ) SOLD I've sorted the airbag light :cheesy:
1998 3.0 V6 SE coupe in Diablo Red ( my baby ) sold
2006 206 1.4 16v sport in Aegean blue ( wife's shopping trolley :roll: )

2006 BMW e61 535d m-sport :supafrisk: run's for cover :lol:
dirtydirtydiesel
3.0 24v
Posts: 1521
Joined: Sun Apr 28, 2013 11:02 pm
Location: Coalville, Leics.

Re: Air bag fault / warning NOW FIXED!!!

Post by dirtydirtydiesel »

dirtydirtydiesel wrote: Sun Oct 02, 2022 3:36 pm Right all.

I can finally bring this saga to a conclusion & hopefully help out future 406 owner's :cheesy:

Only took me three years off & on but she's fixed :cheesy: :cheesy: :cheesy: :cheesy: :cheesy:

Turns out that the 'new unused' airbag ECU I bought was as duff as my original, this lead me up the wrong path believing that the airbag ECU was good & my fault lay elsewhere. Hence my struggles for over the last two years :roll:

The guy who is buying my car has a much worse condition 406 that we tried my two airbag ECU's in (& they threw up the same fault as in mine)

So we tried his in my car & :P
All the lights test & then go out
HAPPY DAYS :cheesy:

So what caused the original issue, having had a read up on airbag ECU faults it's more common than you would think.
If the battery goes low (due to standing) when you go to start it. If you don't wait for the airbag circuit test & the lights to go out.
It can cause a spike upon startup & this blows the capacitors in the airbag ECU :roll:

So there you go another one saved to go on for years more service (after all the work I've done to her)

Thanks for all who have tried & offered to help throughout this saga Doggy & frog to name a few :D

Cheers for now DDD.
2002 110 HDi estate, Rapier in monaco blue! ( found quite a bit more power :cheesy: ) SOLD I've sorted the airbag light :cheesy:
1998 3.0 V6 SE coupe in Diablo Red ( my baby ) sold
2006 206 1.4 16v sport in Aegean blue ( wife's shopping trolley :roll: )

2006 BMW e61 535d m-sport :supafrisk: run's for cover :lol:
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Doggy
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Re: Air bag fault / warning

Post by Doggy »

dirtydirtydiesel wrote: Mon Oct 03, 2022 9:42 am To any Mod's still out there that have the ability
to edit / remove posts.
My last three post's (not including this one) if you read them are slightly duplicated.
Only the last one wants to stay, if you could remove the two before it (if you catch my drift) & this one.

Also you can now edit the title (I tried :roll: ) to add
NOW FIXED!!!

Many thanks DDD.
All done. I'll remove this one in a day or two.

Good work sorting it out & posting the results.
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
frog
2.0 Turbo
Posts: 378
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Air bag fault / warning

Post by frog »

Congratulations! Well done! You did not give up :cheesy:
dirtydirtydiesel wrote: Sun Oct 02, 2022 3:36 pmIt can cause a spike upon startup & this blows the capacitors in the airbag ECU :roll:
Any chance that could be repaired by replacing the blown capacitor?
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater - just hit 690.000 kms :cheesy:
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.
dirtydirtydiesel
3.0 24v
Posts: 1521
Joined: Sun Apr 28, 2013 11:02 pm
Location: Coalville, Leics.

Re: Air bag fault / warning

Post by dirtydirtydiesel »

Thanks frog :D

Told you I'd keep at it, if you saw the car in the flesh you'd understand.
When the new owner first saw it he said quote (ah man, you can't break it for spares it's too nice)

I can't believe all my struggles have been due to being sold a 'new in the box, dud :x '

If that had worked back in March 2020, we would never have been in touch :lol:

Yes, they can be repaired in the UK for £55.
But now we have a good one in it & you can buy used for £20 ish so if we need another we'll go down that route.
After all it's a power spike that caused the issue, not wear & tear :roll:

Hope you & your family are well :D

Take care my friend & thank you for all your help :cheesy:
2002 110 HDi estate, Rapier in monaco blue! ( found quite a bit more power :cheesy: ) SOLD I've sorted the airbag light :cheesy:
1998 3.0 V6 SE coupe in Diablo Red ( my baby ) sold
2006 206 1.4 16v sport in Aegean blue ( wife's shopping trolley :roll: )

2006 BMW e61 535d m-sport :supafrisk: run's for cover :lol:
frog
2.0 Turbo
Posts: 378
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Air bag fault / warning

Post by frog »

frog wrote: Tue Oct 04, 2022 9:15 am Take care my friend & thank you for all your help :cheesy:
You're welcome :wink: But in the end, all the schematics I gave you were pretty useless :( as it turned out the box itself was broken.
Hope you & your family are well :D
Thanks, we're doing fine. Kids are growing older (and so are my wife and I...) Worried for the day the kids are all having their own car (but dad can repair :roll:)
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater - just hit 690.000 kms :cheesy:
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.
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