My 1992 240 stranded me Saturday night. Car was running fine. Then suddenly all the idiot lights come on at once. Over a period of 15 minutes or so some blink out but most stay on. Then, the dashboard illumination and headlights start to get dimmer and dimmer. Radio finally cuts out. The gas and temperature needles slowly drop to off (bottom) position. It's as if the car's electrical system is dying in slow motion. Then car begins to slow no matter how much gas I feed it with accelerator pedal and slowly, over the next few miles, she dies. Car will barely turn over due to dead battery. If you charge the battery, the same thing happens again. Seems like classic signs of alternator trouble to me.

Had it in to a mechanic today (who knows nothing about Volvos new or old). He charged the battery, started her up and put a meter on the system. "Your alternator is charging right at 14.2 volts, which is where it should be. It's running fine. I have no idea what's wrong." When I pressed him to speculate, he suggested that it might be some weird issue where the alternator stops working when it warms up. Or maybe the voltage regulator, he said.

Anybody seen anything like this before or have a clue? Advice?