SRS airbag warning won't reset - error in light circuit

[zwieback]

2002 V70 base model.

Here's the sequence of events:

- Instrument cluster failed completely
- Removed and reflowed solder around main components (didn't unhook battery first)
- Instrument cluster works again but SRS airbag warning is always on.
- Mechanic unable to clear SRS code with professional scanner tool, message is "airbag light circuit failure"

I assume the airbag module can't communicate with the light in the cluster but there's nothing wrong with the airbag itself.

Any recommendations? Should I try to reflow the solder some more or is there a specific circuit/component on the instrument cluster PCB I should be looking at?

My other option is to send in the cluster for repair/exchange for $150 or so. I'd be fine paying that if there's some confidence it'll fix the problem


Thanks,
Andrew

[chrism]

I also replaced the DIM on my 2003 V70 a few years back without disconnecting the battery. That probably would have been OK, but I also made the mistake of starting the car to relocate it in my driveway while there was no DIM installed. I'm thinking that was my mistake. So when I did installed the new-to-me DIM it all worked OK except the SRS light was illuminated. This lead me to conclude that the light itself is part of the monitored system, so when I started the engine with no DIM installed the absence of the light caused a fault to be recorded. Then when the new DIM was installed and the engine started, the SRS light illuminated due to the fault being recorded and not yet cleared. I drove the car to a well equipped independent Volvo shop and they cleared the code for me.

The fact that your SRS light is illuminated may not be a bad sign. I would be more inclined to question the system your mechanic is using to clear the fault. It may not have been able to handshake with the car deep enough to clear it. Is this a very Volvo savvy mechanic and do you know what type of scanner he/she used?

[zwieback]

He seems very savvy and works on Volvos a lot. He used an impressive looking diagnostics tool made by Snap-On. However, I might talk to the dealer next, see what they would charge to do the diagnostics with the official tool.

[doublebug]

You need to clear codes in both modules DIM and SRS at the same time.
While clearing codes message on the dash should disappear for 10 seconds in a case SRS module is not locked.

[equiprx]

I recently purchased a 2002 V70, 2.4t and I needed a few extra USB ports which I installed next to the cigar lighter.
After that I also got a SRS code and was told by the dealer that is common when working on the dash components.
She told me I should be able to clear the codes using my scan tool.
While I was trying to clear the codes, I must have bumped the hardware I installed because I smelled and saw smoke coming out of it.
I immediately shut everything off that I could then ran into the garage to get my Torx screwdriver to pull the dash apart.
When I took it apart I saw that the part I added made contact with the connector on the PC board behind it.
It fairly ruined the part I installed and the PC board was very sooty and had a small burn mark on the plastic portion of the unused connector.
I have never been able to erase the SRS code and I still need to find a way to add multiple USB ports in the car.
The circuit board doesn't appear to have any visual damage but I know that doesn't mean much.
Any advice on how to check on the health of the PC board would be greatly appreciated.

[abscate]

Pull it out and send some pix, but once you burn stuff on even 2000 era boards it's probably beyond economical repair

Which board are you referring to here?