2003 307SW 2.0 HDi 90 Airbag Fault

[ca2n]

Hello all,

I am hoping to get some advice about getting rid of the airbag warning lights on a 307SW.

Vehicle: 2003 Peugeot 307SW 2.0 HDI 90 (RHY, Bosch)
Issue: Warning lights on dashboard - airbag warning light and front passenger airbag deactivated light (although the front passenger airbag was switched on)

Results of diagnostics:
Scanned using PP2000 24.29 with (cheap) Lexia dongle (the one without an optocoupler)
- No reply received from airbag ECU (same outcome was achieved using a Launch scan tool)
- ECUs that replied include: BSI, Multifunction display, Radio, Instrument panel, COM2000, Engine ECU, and ABS or ESP ECU



BSI scan shows four faults:

• Permanent fault. Communication on the DATAB wire of the air bag ECU
• Permanent fault. Communication on the DATAB wire with the column height ECU
• Permanent fault. Communication on the DATAB wire with the engine wiring housing
• Permanent fault. The outside temperature sensor

COM2000 doesn't show any faults with PP2000 scan



Steps taken so far to remedy the fault and their results:

1. Used airbag ECU (Siemens 9650109480) fitted - same airbag warning lights illuminated, still no reply from airbag ECU using PP2000
2. Another used airbag ECU fitted - same airbag warning lights illuminated, still no reply from airbag ECU using PP2000. (So that's three airbag ECUs fitted now with similar outcome)
3. 50VOR connector on airbag ECU 6570 unplugged/plugged, 2VBE and 2VMR outboard connectors on (CV00) COM2000 unplugged/plugged, Fuse 16 (F16 BSI1) in the glovebox checked OK - same result as above

BSI reset procedure from here followed each time disconnecting/reconnecting battery.

Some screenshots from SEDRE of the related wiring:






The last time the two warning lights showed up was when the two outboard connectors 2VBE and 2VMR on the COM2000 were incorrectly seated. This was a while back and once the connectors were reseated, the warning lights extinguished.

This time around, the issue arose after the car wouldn't start due to a faulty in-tank electric fuel pump. Attempts at starting were made until the battery died which could have potentially damaged the airbag ECU, as reported in a similar 406 case. Work was done by a garage to get the in-tank fuel pump running again - according to them, some rewiring was done. The garage wasn't keen on investigating the airbag issue as their scanners had issues communicating. We were likewise not keen on getting them to do further investigation as the fuel pump fix took several weeks (and convincing them that the car actually has an in-tank pump).

Apart from replacing the COM2000 unit, I'm not sure where to go next.

Any advice is much appreciated!

[Huskyxantia]

Id try a replacement one and see if that helps might be the quickest way

[ozfrog]

This time around, the issue arose after the car wouldn't start due to a faulty in-tank electric fuel pump. Attempts at starting were made until the battery died which could have potentially damaged the airbag ECU, as reported in a similar 406 case.

That was scary reading. I have had an immaculate low kilometre 2003 406 HDi sitting in my backyard for some 4 years. Problem? Airbag light is on permanently on the dashboard. The car's previous owner had an expert mechanic who couldn't be bothered(?) to fault-find this. His solution was to remove the idiot (warning) light from the dashboard.

And reading that tale, I'm not looking forward to either trying to fault-find it or pay someone to do it for me.