Another Electrical Gem

Here I go with another electrical problem. My 87 911 Coupe has developed(?) another electrical problem. My cold air fan will now only operate with the headlights on!! This can't be right! Last month a couple of auto electricians "fixed" my failed windscreen washers by throwing in another pump and splicing it into the wiring loom. The headlight washers then failed....so they made another connection and they work fine but now this problem........I'm wondering, given that the headlight washers only work with the headlights on, if these guys have caused more circuitry wizardry and rendered my cold air fan inoperative other than when the headlights are on........or am I imagining it and there is some really bizarre reason why the fan should only work with the lights? Time for the analyst again.............

Hi Bonnie, I had a very similar problem, but as you know electrical issues can look the same, smell the same, but not be the same. At any rate, after going through much of what you already have, it turned out to be a cracked fuse block. The crack was on the back side, which made it very hard to track. We spliced things into the bad one just to have something else fail. I smelled plastic burning in the trunk and asked a friend to come over (he had better sinuses). We removed the block, changed it out and no problems since the swap. Good luck and hope that this helps.