I'm pretty sure I've read prior posts about this issue, but for the life of me I can't find them here so I'm sorry to be asking a question that's probably been asked a hundred times...

I finally inherited my father-in-law's '93 244 Classic with 82,000 original miles, meticulously maintained and lightly driven. It was a diplomatic sales 240 that was shipped to DC from Sweden and has subsequently spent it's life in DC, Mexico City, and then Miami where it was semi-retired. I posted detailed photos of it a year ago or so, but can't seem to find that post anymore. It's the ruby red with black leather interior, and though it's badged a 'Classic' in the back, and has the scorpius rims, matching painted mirrors/headlight trim and wooden dash trim (all characteristic of the 'Classic'), it does not have the matching painted grill or a numbered badge on the dash. So it's not one of the numbered 1600 Classics. It was manufactured in February '93, so though it was near the end of the run it's not one of the very last ones.

Anyway, all of that said, it does have a few minor items that need to be fixed. The most pressing is the dead odometer/trip meter, which I suspect is the gear though I haven't opened it up yet. Also, the fuel gauge does not work at all, and the temperature gauge works only intermittently, probably about 40-50% of the time. I thought I had read a couple posts in the past that there is a little voltage regulator or something back there that is usually the cause when both those gauges aren't working. I took it to a local volvo mechanic to have a look, and he thought it was the circuit board though he didn't have much time to look it over. I also picked up a replacement speedo cluster for parts out of a '93 wagon.

What are the most common causes of the fuel/temp gauge fault, and what spare parts should I be looking to scavenge out of the donor cluster?

Sorry for the long post, and thank for any assistance.