'90 Civic electrical problem

10 amp fuse for courtesy (running) lights keeps blowing out....but
headlights and brake lights are OK. Anyone know where I should look to try
and trace out the problem? Is this a common problem? Thanks!!

 

If you mean the parking lights, you have some work ahead of you. Those
lights are connected to a ton of places, including all your dash lights
and instrument lights etc.

I'd start by removing the parking light bulbs, including the ones in the
rear. Sometimes when bulbs burn out they become short circuits. Then I'd
disconnect the dash lights brightness controller, that should isolate a
good chunk of the circuit.

 

I don't know if this is relevant, however, I have an '88 Civic and had
problems with my running lights as well. In my case, they simply stopped
working. After a little while I noticed that moving the head light switch
around caused them to flicker on. I disassembled the head light switch,
cleaned up the contacts with some 400 grit sandpaper, lubed it with some
silicone grease. They have been working now for about 3 or 4 years now
without any problems. Your head light switch may need a similar overhaul.

Eric