Found out why my aux fan stopped working
96 XJ 4.0 Auto...
Check engine light came on, a/c stopped working. OBDII said Radiator Fan Circuit. I put 12V to said fan and it spun nicely. Checked the relay and fuse per the owner's manual's layout diagram and could not find a problem.
A shop finally tracked the problem down ---- to the other end of the Jeep. Seems one of the cheapo WalMart fog lights I bought to use as backup lights had a direct short in it, which, when it popped the fuse, tripped the CEL because the backup lights are on the same circuit as the aux fan.
The owner's manual, as well as the shop manual he had, show the wrong fuse location in the relay center for the aux. fan. The shop ordered an online wiring diagram and found out that there are at least three variations of the relay centers on 96 XJs. The mechanic replaced the blown fuse and everything worked fine - until he put the Jeep in reverse to back out of the shop, when the fuse blew again and the CEL came back on, etc.
This had him then checking out the back up light circuit and he found the short inside one of the lights.
Once the short was fixed and the fuse replaced, everything is crackerjack again.
So there you go. Mystery solv-ed!
HOWever, I did spot one potential trouble spot-- the wiring loom that goes down the front of the engine on the left side down to the O2 Sensor / CPS area was touching the exhaust manifold, which had melted the plastic loom protector and burned the insulation off one of the wires inside. Good find, now fixed.
96XJ Sport 4.0 Auto Chrys. 8.25, 1-3/4" BB. 242,776 miles and developing a bad rattle.
Last edited by CraigAllen; 06-09-2007 at 02:11 PM..