B78 Picasso airbag light

[justinzak]

Having a chew with a Picasso. No fault codes and all resistances look good. Initially had a passenger seat resistance code but after cleaning the plug and clearing codes, no code will return. Drivers airbag is correct at 5-6 ohm. Any clues before I blame it on the module?

If I unplug any airbag, it will successfully make a fault code also. Also checked diagbox, no difference.






Any clues appreciated thank you

[RichardW]

Airbag switch line looks odd, I'd have thought it should be 0 or infinity? Try some WD-40 up it and turning it on / off a few times to see if it clears?

[justinzak]

The airbag switch needs to detect open and short circuit so I thought an ominous ohm value would be expected, but will check the spec sheet to see if you're right

[wheeler]

The deactivation switch will normally have 2 different resistances for on & off. As you pointed out this is so the system knows if there is an open circuit or if the switch was unplugged for example.

[justinzak]

Checked back a day later to see if any codes had come up, nothing yet. Can see in airbag ECU that the airbags are disarmed so what I ended up doing was locking and unlocking the ECU, and this finally took the airbag warning light off.
Still have an issue with the passenger airbag deactivation light being stuck on. With a potentiometer, I discovered that 100-800 ohms is the allowable range for the switch without producing a fault code. However, no resistances in this range would take the light off, all buckles secured etc. Battery disconnect, bsi reset, light stays on.