Airbag lights off on startup

[CraigIrl]

I just had my NCT( Irish equivalent of MOT) and it failed on the airbag lights not self testing on startup. The fuse in the box inside the cabin is fine so now I've no idea what to do. Any ideas??

 

[MicKPM]

Proberbly due to the bulb being removed/broken as its in 'fault' status. We've got all this to come starting in January.

Firstly we need to confirm this so go to the car, put key in ignition then BEFORE turning the key press and hold the wiper stalk button. Now turn the key but don't start the car. The clockset will go into self test mode making the needles jump and all the lights come on. The important question: Does the SRS Lamp come on?

Mick

 

[CraigIrl]

The one that reads air bag off comes on

 

[MicKPM]

Not that one, that's to say the passenger bag is off when you put an ISOFIX child seat in. The one that's a picture of an airbag and seat. I'm on my blackberry now so can't Google image post one for you.

 

[CraigIrl]

Nope that didn't come on. That one is above the other one

 

[MicKPM]

 

[MicKPM]

Right, they've destroyed the SMD then and a new unit is required. Then diagnostics to find and eventually fix the issue I'm afraid.

Fooking pikeys - personally I hate this!

 

[CraigIrl]

That one isn't lighting up. I presume I should check the bulb then. I'm sure it used to light up so maybe a blown bulb

 

[CraigIrl]

What's an SMD just outta of interest

 

[MicKPM]

They're SMD's not bulbs and rarely blow! Could be a broken wire or poor connection at the clockset I guess as the lights are triggered by +12v down each line via the UCH. Bulb test was step 1 and I'm afraid step 2 is diagnostics to try and establish a connection to the ABS module and see what's wrong. Could be the entire system isn't working but I'd expect to see the SRS MIL on all the time hence I believe its been tampered with to knock the light off.

Mick

 

[MicKPM]

Oh and SMD is a Surface Mounted Diode... Small, bright LED

 

[CraigIrl]

My car doesn't have ABS as its a 172 cup

 

[JackJack]

Think Mick meant airbag/srs module.

 

[CraigIrl]

Ah ok. Well this will be fun as here in Ireland Renault are useless for my car as it was never sold here and are clueless.

 

[MicKPM]

My bad, yes, I meant SRS not ABS.

Anywhere with semi-decent diagnostics of the Snap-On variety will be able to reliably tell you wants wrong with the SRS. Easiest way to resolve the clockset SMD issue is to post it to me and I'll fit you a new one OR replace the clockset and re-run the bulb test.

 

[CraigIrl]

Well I'll get it scanned and see what the fault is and if my regular mechanic can't fix it I'll send the clocks to you

 

[MicKPM]

If they cannot establish a connection with the SRS then the system itself is in fault but if he can then go with a wiring fault at the clockset or the SMD for the SRS lamp being tampered with. The clockset won't cost much to fix, just the cost of the SMD and a beer... probebrly cost more to send both ways than the job's worth TBH

 

[Dink]

Oh and SMD is a Surface Mounted Diode... Small, bright LED

just a little point SMD stands for Surface Mount Device

 

[MicKPM]

Yes but an "SMD" can be many things... Capacitors, Resistors or any other component that can be mounted to a PCB are classed as SMD's but in this case, the SRS LED its a SMD LED or Surface Mounted Diode which is a specific type of small form, ultra bright LED.

 

[Dink]

but a diode doesn't always emit light

SMD LED is correct term for it

 

[pendulumx]

Do not derail thread with pedantry, kthx.