Grand Cherokee 2001 cooling fan running

I believe the fan is a reversible one like the heater fans with two wires going to it, but could be wrong on a GC. If so, it could short and overload or overheat the relay fusing it on.

The story is plausible. Relays usually need an overload to fail 'on'.

Mike

Guess your grill is harder to remove than mine. :/ As for the temp sensor, from what I understand, one of them is in the fan.

I kinda doubt fan motor was shorted out if it was running normally otherwise. Relays do go bad but you cannot make as much mney on labor changing one of them as a fan. I think he got taken.

----------------- TheSnoMan.com

The relays often fail, and seems to me when ours failed with the fan on we also needed a new fan as the motor was drawing more current then it should. Bearings probably going out. Our '99 has been in the shop at least 3 times for this issue. It is not the sensor, but usually the relay, which they get plenty of lab or for changing as it is behind the headlight and I believe the bumper fascia needs to be removed. Does not sound like a "rip-off", just a common expensive Jeep malady.

It seems to me that if the relay sticks that easily then it is under rated for the job and fails with time. Relays can arc a lot under high current and DC loads and if the contacts are not sized properly for this load they will fail with time. If this is really such a common problem, they should have fixed it with a higher capacity relay rather that keep sticking you with replacing a marginally rated one. I have had a lot of cars over the years with electric fans and never had the first one with control relay issues even after 11 years of service. Properly sized the fuse will blow before the relay would burn and they fact that no one mentions fuses blowing tends to support a design flaw with a improperly sized/rated relay. (likley to save a few pennies when building them)

----------------- TheSnoMan.com