AirBag light on???????

[bcfc]

Air bag light came afew days ago any ideas wot it may be???

[Sloucher]

Almost certainly this'll be a side airbag curtain warning. There's probably nowt wrong with the airbag, its all down to a high resistance in, or disturbance to, a connector under the driver's seat. Unfortunately even when you cure the problem, the durn light stays on and has to be reset using Alfadiag and suitable interface cable.
I know this 'cos mine came on last week, but my interface cable doesn't have the connection on pin 3 to the airbag computer, so I had to get my local indie to reset it.

HTH

[rarebear]

solder a wire from 3 to 7

[alfiGT]

If you move or adjust the seat while driving it can also cause it to come on

[Probusterrace]

Can also be due to a loose connector inside the Rear quarter compartment (inside the boot).

My local main dealer re-set mine FOC.

[Sloucher]

Originally Posted by rarebear

solder a wire from 3 to 7

Do you mean at the car end of the OBDII to USB lead rarebear? Problem is, the OBDII connector on the end of my lead doesn't have a pin at position 3, just a blank space . Thanks for the info tho'.

[jomor]

you can cut a piece of a resistor terminal and solder it at the empty position of your connector, and then you can solder it to pin 7

[thedoctor]

This happened me just the other day after moving the seat. Unplugged and reconnected connector and the light went off. Mine's a 2003 156 - I think the post-03 ones reset themselves if the fault is resolved. Reading these boards regularly has proved worthwhile - I knew exactly where to go! So thanks for that guys

Anyone know why there are empty connectors under both front seats? Am I right in thinking they're there for diagnosing AB problems?

[Probusterrace]

Originally Posted by thedoctor

Anyone know why there are empty connectors under both front seats? Am I right in thinking they're there for diagnosing AB problems?

What spec car have you got? Have you got leather heated seats?

[thedoctor]

It's a Lusso. Leather seats but, as far as I know, no heating. And I'd like the think I'd have noticed that! There's a white square connector under both seats and an extra small one under the driver's seat.

[rarebear]

hammer a big paperclip flat and insert that in the empty spot on 3 , then solder a wire to 7

(or buy my lead with all 16 pins and functions tested)

[Sloucher]

Thanks to jomor and rarebear - durn good ideas. My task for this evening methinks!

Let you know what happens.....

[Sloucher]

D'oh........

Made up a new pin from some suitable wire beaten flat, positioned it in position 3 in the connector, went to bridge it to pin 7 when.....

I noticed that pin 7 doesn't actually connect to anything on the circuit board in the connector shell, its just an unconnected pin. Is the idea just to connect the ecu 3 and 7 connections together when the OBDII lead is connected? Or does it look like my lead is gonna have to be replaced with one of yours rarebear??

[bcfc]

Looked under drives seat and disconneted the wires, plugged back in, light has gone out,has been out all day happy days!!!!!

[twig]

airbag faults reset themselves on cars from late 2002 onwards, mines a 52 plate and after I fixed the side curtain airbag connector in the boot it self reset and has not come on in 3 years.

[rarebear]

Originally Posted by Sloucher

D'oh........

Made up a new pin from some suitable wire beaten flat, positioned it in position 3 in the connector, went to bridge it to pin 7 when.....

I noticed that pin 7 doesn't actually connect to anything on the circuit board in the connector shell, its just an unconnected pin. Is the idea just to connect the ecu 3 and 7 connections together when the OBDII lead is connected? Or does it look like my lead is gonna have to be replaced with one of yours rarebear??

if you have an universal meter , measure the resistance between 7 and ground 4,
7= K line must be connected to the circuit in the connector, its the one that
talks to the car's ECU !!!!
I got you a nice new tested lead ready for shipment

[156Chris]

Originally Posted by twig

airbag faults reset themselves on cars from late 2002 onwards, mines a 52 plate and after I fixed the side curtain airbag connector in the boot it self reset and has not come on in 3 years.

Well you say that ... my '52 plate (156 JTD) does reset it self ... my my sister in laws '04 147 JTD have to be reset with alfadiag

[rarebear]

Originally Posted by 156Chris

Well you say that ... my '52 plate (156 JTD) does reset it self ... my my sister in laws '04 147 JTD have to be reset with alfadiag

it depends on the airbag crash sensor type, Allied or Siemens or MM and a few more, and the MY (model year)
the car manufacture date is not totally relevant, they can insert any sensor they have in stock at that moment during production.

[Sloucher]

Originally Posted by rarebear

if you have an universal meter , measure the resistance between 7 and ground 4,
7= K line must be connected to the circuit in the connector, its the one that
talks to the car's ECU !!!!
I got you a nice new tested lead ready for shipment

Whooops! Yup, you're quite right rarebear. I didn't see the connecting track as it was hidden by the main circuit board - must get these glasses checked!! Sorry though, it means I'm no longer in the market for a new lead! Mind you, my local indie has already reset the airbag ecu for me already, but I'll be ready for it next time.....and I just know there'll be a next time!

[rarebear]

Originally Posted by Sloucher

Whooops! Yup, you're quite right rarebear. I didn't see the connecting track as it was hidden by the main circuit board - must get these glasses checked!! Sorry though, it means I'm no longer in the market for a new lead! Mind you, my local indie has already reset the airbag ecu for me already, but I'll be ready for it next time.....and I just know there'll be a next time!

so this time I shot in my own foot !! but good for you... there's no better satisfaction
then to master the damn electronics yourself !!!

[fillou]

Hi,
Could someone post a pic with the connectors in boot? Where do i have to focus? The airbag lamp on my 156 (facelift model 2005) is now always on, but before that and for a couple of days it was on/off (something like auto-reset).
I've tried KWP71 with my cable and the error is
Read diagnostic fault codes :
Bytes received: 21 67 05 9A ED
DTC: 0x21 = 33
state : 3
type : 0x07 Too high value
condition1 : 0x05
condition2 : 0x9A
counter : 0xED
21 Ignition circuit, window bag, driver side,
33 Drivers Side 1st Stage Head Curtain Airbag Front

I believe that if i unplug,clean and restore the connections then the error should be cleared.
Thanks.
Nikolas