Hello everyone!

I need help! Yesterday my 2000 Grand Cherokee Laredo overheated.
It went all the to 280 (i think -- the max).

What's happening is that if I keep the A/C ON no problem, the temp. Gets normal by if I turn the A/C off, it overheats.

What can that be?? Does anyone here had the same problem before?

Thanks

 

Does the Grand have an electric fan like the xj ??

Could be when you turn the a/c or defrost on it signals the electric fan to kick on.(as it should) The fan may not be kicking on with the a/c or defroster off. The problem could be in the electric fan thermostat ?? Not familiar with the Grand.

will follow this post to see if I'm close...

 

Post in the grand cherokee section and you may get an answer...

 

I agree. Check electric fan or fans for proper operation.

Turning on A/C will force all fans to come on if they work.

The electric fan or fans should come on with A/C off when temperature reaches a certain higher point for additional cooling.

If they don't, check sensors and relays.

 

Hey guys!! Thanks I'll check out the thermostat.

 

dont grands have one electric cooling sounds like coolant temp sensor issue not turing fan on, locate cts unplug it and start it if with ac off fan comes on replace the sensor work this way on most vechicles

 

I bought a new sensor but I haven't replaced yet.

However something weird is going on...

Thos morning I left my car on idle too see what would happen with the temperature and I noticed that the fan was OFF. When the car started overheat the fan came on full power, I looked at the gauge and it was a quarter higher than normal, couple seconds later the temperture was normal and I also noticed that the fan was still ON but slower.

My question is, is the fan supposed to be ON all the time in a lower speed and speed up whenever it needs or not?

Because it worked fine this morning do you guys think is there any chance of fan problems instead of thermostat?

Thanks guys!