I may well have been very lucky, but thought it might help others faced with a similar problem.

Just picked up the fatty from the body shop after having it's arches and rear sills done, to be told that the air bag warning light had come on and couldn't be reset. Suspect they were using a surge protector on the battery when welding, rather than disconnecting the battery. Would this have caused the fault?

Anyway, read the codes with the IID tool and the '0xB Battery Disconnect Unit 1' fault appeared, so cleared the fault, but was left with the SRS airbag light lit. When I re-started the fatty the fault reappeared on the IID tool as well. As others have seen, on startup the SRS airbag indication came on for about 1/2 a second, went off for 1/2 a second and came back on and stayed on.

Thought it might be either the SRS Battery Dissconnect Unit or the SRS ECU that had latched up, as experienced by others, but decided to keep it simple to start with and removed the battery and put it on charge (although the IID tool reading was around 12.6v at rest) and had a good look at the cables and SRS wiring, disconnecting and reconnecting the yellow cable block. Saw nothing obvious though.

Waited for an hour, and put the battery back in. On starting up the SRS airbag light and fault were still there (following the same flashing pattern as above), so used the IID tool to clear all the faults this time while the engine was running. Thankfully the fault disappeared and the SRS airbag light went out.

Stopped and started the engine a couple of times, but so far all good  David

2012 Range Rover Westminster 4.4TDV8
2004 Range Rover Vogue 4.4 V8 (LPG) (Not quite gone)
2021 Mazda CX-5
2003 Porsche Boxster

Thank you David, the tip about using GAP IID whilst the engine was running worked for me today

MY 2004 Petrol 4.4 BMW engine