Electrical question

i turn on the front windshield defroster on my 90 xj and the fan for the radiator turns on at the same time and stays on untill i turn off the defroster if i put it on any other setting this does not happen anyone have a clue why or if that is normal.......

If I remember right, when you go to defrost it actually turns on the AC to dry out the air. Anytime the AC is on, the AUX fan runs.

old_man said:

If I remember right, when you go to defrost it actually turns on the AC to dry out the air. Anytime the AC is on, the AUX fan runs.

Click to expand...

Correct.

And when the a/c turns on, the aux fan turns on.

ok well my next question is i put a new motor in my truck like 2 years ago and i noticed after i hooked everything back up that the black wire that comes off the top of the ac condsor was burnt and disconected does this mean that the ac unit is no good or is ther just a short somewhere