I need help haha. Neither my excellent Volvo specialist mechanic nor I with my Googling can figure out what is causing my A/C + radio + wipers + power mirrors + horn (etc.) to not work (and my SRS light to go on). This problem started happening about a month ago intermittently - would happen when I was driving, stick around for 20 minutes, then go back to normal. Then it started happening all the time, so I took it to my mechanic, who initially suspected the ignition switch but jiggling the key didn't do anything. He said he went digging around the fuse box for an hour or two and at some point, everything started working again, and he didn't know why, but couldn't troubleshoot any further because it was working. That lasted about a week, and now it's back. He said the only other thing he could suggest would be to replace the fuse box, but that's a part that may or may not be available.

I decided to try fixing it myself based on stuff I read online about this issue, so I took out the cluster, refloated all the solder joints, and installed a new ignition switch. This solved nothing.

Does anyone have any thoughts? Everything I've seen so far says multiple electrical problems point to a bad cluster or a bad ignition switch. Maybe I missed something?

Thanks in advance.

 

see if the volvotips.com web site has a wiring diagram that may show commonalities like ground points, relays etc.