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So I was driving my car today, to and from school, about a 3 mile drive, city driving, 25-30mph. Got back home in about 15 minutes and left the car idling for another 15 when my engine overheated, shooting antifreeze from out the reservoir. So I checked the fuses, sure enough, the cooling fan fuse (30A) was burnt out, and I got it replaced. I also checked the cooling fan connectors and wires just to be on the safe side. What i found was frightening! The the plastic casing of the wires had melted and were semi-fused together! Pretty badly, but was able to separate the black from the yellow up to the point where it runs behind the headlight. The wires were definitely fused and tangled form the connector for the first foot. The rest up to the point where it runs behind the headlight, the plastic was melted, but not fused together.

So what can cause the wires to do this? I wouldn't say they are 'fried' since that would imply that the wires are burnt out and non-operational. Only the plastic casings of the wires were melted, the copper of the wire was still fine. My engine isn't modified, except for headers. My best educated guess would be maybe my fan is working overtime from me blasting my stereo system (1000W subs). And if this is plausible, would a capacitor for my system fix this problem???

When an electric motor is powered but cannot spin (something stuck in it, or bearings seized or anything) it does not provide itself with an internal resistance (CEMF, counter electromotive force) so it draws more current than it should if it were running normally. This is the same phenomenon that causes spikes in all electric motors at startup, sometimes even up to or beyond 4x the rated amperage.

So, make sure your fans spin freely by hand, apply 12v directly to them for a second to make sure they run properly, and the just replace the wiring.


If the overheat was bad, you might have head gasket issues, but don't count on that just yet, these motors are super robust.