Nutinelse2do wrote:
Sounds like you are drawing way to may amps through the wire to me, and I would also guess there is no relay or in line fuse. Maybe also that the wire is way to small.
You're going to want to find out how many amps the fan draws because that will tell you what size wire and relay to use and you should be using the switch to turn on a relay, not running the fan.
Also I would not think that is a trans cooler, more like a fan to help cool the engine. But without seeing it or more details hard to say.
Hope this helps ..
Yeah x2. Too much amps going through the wire & switch. Also check the fan and make sure it is in good operating condition... No shorts, etc.