My mechanice replaced the entire speedometer head in my 1991 Volvo 740 SW. Since then,
when I turn on my headlights, the front & rear windshield wipers are on, & cannot be turned off
without pulling the fuse. Also, the front headlight blinks when I turn on my headlight. Mechanic says it is NOT due to his repairs, but I question that.
Also, the gas gauge indicator light for 'empty' is constantly lit, even when tank is full, half, etc.

I think some wires have been crossed. H E L P!!

 

Not sure if the rest are related but He might have done something for the low fuel light to stay on.

Maybe he chaffed a wire or something like that.