Grand Picasso, seatbelt lights going mad!

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gully.moy
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Joined: 12 Dec 2014, 20:27

Grand Picasso, seatbelt lights going mad!

Post by gully.moy »

My Zafira died so I quickly found a cheap C4 Grand Picasso. It's a 1.6 petrol 59 reg VTR+. During my test drive with the private seller, the rear seatbelt warnings were going mad, beeping at us loudly and flashing on the dash. They would go on and off randomly in varying configurations and sometimes go off when fiddling with the belt socket. The very rear seats seem to illuminate dash lights but don't cause a beep? We just plugged them in with nothing on the seats to shut them up. "It's a new one on me mate" he claimed.

Anyway, I was desperate and had no return transport so I hangled him down and left with my dodgy new ride! Obviously it's annoying but is it an MOT failure to have your car to remind you to fasten a seatbelt around nothing? I've read some cars you can silence alarm but still get dash lights which could be acceptable.

Ideally though, of course I'd like a permanent solution. I don't care about them working as we always use seatbelts anyway and don't need reminding, but I haven't found any easy hack to disable them? Does anyone know any? Could I get/make a seat occupancy emulator or could that affect airbags?

Failing that maybe I could change a part myself? I've seen reports that there's a microcontroller in the buckle stalk which is a common problem. Some have blamed these symptoms on the stalk, but it seems to me that the sensor as to whether the buckle is plugged in works fine. Instead, the car seems to think that there's someone in the seats when there isn't - seat occupancy sensor? Could it still be the stalk as suggested in the link below; I suppose it would fit with the fact that fiddling with the buckle can temporarily resolve the issue, but I don't understand how that could be affect occupancy sensing?
http://c4owners.org/plugins/forum/forum ... php?118333

Otherwise I'll have to get it done professionally which I guess will be very expensive. Any idea what might be a fair price range?

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GiveMeABreak
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Re: Grand Picasso, seatbelt lights going mad!

Post by GiveMeABreak »

Pop the Vin up for me here and I’ll take a look at the particular system on your Vehicle.

gully.moy
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Re: Grand Picasso, seatbelt lights going mad!

Post by gully.moy »

VF7**************[VIN obfuscated, can be read by forum staff]

Thanks a lot

RichardW
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Re: Grand Picasso, seatbelt lights going mad!

Post by RichardW »

From what I remember the rear seats don't have occupancy sensors on them - just buckle sensors. So even if someone is sitting in the seat, and they don't buckle up the light goes out. The beeper only goes off if the belt is unplugged when it has previously been plugged in. Did you plug in the rear belts to check operation when you were looking at it? If they've not been used they could be a bit sticky - just plugging them in / out a few times might be enough to get them to behave.

gully.moy
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Joined: 12 Dec 2014, 20:27

Re: Grand Picasso, seatbelt lights going mad!

Post by gully.moy »

Ah, thanks Richard - I think it's beginning to make sense then. I didn't plug them before it started beeping when test driving. But in that case, a stalk fault (buckle sensor) would make sense. It must be mis-sensing q plugged in state and then thinking the buckles have been unplugged. Hopefully GiveMeABreak can confirm?

Does anyone know if this would be an MOT fail? Or if the buckle stalks would be DIY replaceable?

admiral51
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Re: Grand Picasso, seatbelt lights going mad!

Post by admiral51 »

This is just me thinking, but being an 11 yr old car we have no idea how much use the rear seat belts have had, i would maybe try spraying some electrical contact cleaner ( not WD40 ) into the stalks and on the buckles and give them a bit of a work out.
As for the MOT, my understanding is that all seat belts if fitted need to be secure and the latch/release mechanism needs to be in order as is the restraint locking when pulled.
The stalks are AFAIK an easy DIY replacement i do not believe the rears have pretensioners in them.

Edit the last bit i do not think they are like the front seat belts in this car ie they work on the locking mechanism alone unlike the front seatbelts ?

Colin

gully.moy
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Re: Grand Picasso, seatbelt lights going mad!

Post by gully.moy »

Good thinking, thanks Colin. I believe the car was idle for a few years before he bought it last June, so this would make sense.

The seatbelts work fine in the ways that you have spoken of, I was specifically wondering about the warning lights with regards to MOT.

Hell Razor5543
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Re: Grand Picasso, seatbelt lights going mad!

Post by Hell Razor5543 »

Based on the fact that the car has been idle for a few years it could well be worth getting the battery checked. C series Citroens have a lot of electronics, and a failing battery can throw up all sorts of weird problems.