A while back I was driving back home from work and had to go through a very congested tunnel, long story short, I found that my car was over heating to the point that I had to pull over as soon as I got out of the tunnel to let it cool down. Once I got home my dad and I looked everything over and saw that the electric fan would not turn on when the temperature started to increase. Something similar happened to us previously and the solution was to replace the fan relay located near the right fender. Replacing this did not solve the problem. We checked to see that the fan wasn’t the problem by connecting it straight to the battery and it worked just fine. The only other thing we could thing of was to replace the temperature sensor located near the thermostat. So we replaced the sensor and the thermostat just in case. It seemed to have been fixed until I drove through the tunnel again and it overheated, not so much that I needed to pull over, but it was definitely climbing above normal operating temperatures. We have also replaced the fuse for the fan that’s located in the power distribution center. My dad says he’s idled the car a few times with mixed results: He’ll idle the car with air-con on and the fan will turn on immediately to help with cooling, he’ll then try it again a while later and the fan won’t turn on causing the temp to rise. We’re really stumped by this one, we’ve replaced pretty much every component we can think of and it still isn’t working reliably. The only other thing I can think of is that the fan has some circuitry on it that may be damaged, but I feel that is unlikely.
2001 Jeep Grand Cherokee Laredo
-Fan fuse in power distribution center
-Water temp sensor
Any advice would be greatly appreciated,