Thermostat?
Asked by Butterbird Feb 09, 2015 at 07:24 PM about the 2005 Jeep Grand Cherokee Limited 4WD
Question type: Maintenance & Repair
I have a 2005 Jeep Grand Cherokee Limited 4.7L. It ever heats on short trips but when
you go on longer trips it is fine until you have to stop then starts to overheat very quickly.
When you turn on the car on it says to service system and service 4WD. Is it the
thermostat. I tried to look it up on the net and every link that was posted not what I
needed. I put specifics in for the search such as year, 4.7L but comes back with wrong
year, wrong model or wrong engine.
5 Answers
The electric fan may not be working. There is a relay/heat sink mounted to the frame up front that fails quite often. When you are traveling at highway speeds the air through the radiator may be enough but when you are stopped or going slow the engine will heat up without the electric fan running. Run the truck stopped and when the temp starts rising look under the hood to see if the electric fan turns on. If it does not, that is your problem.
Thank you for your answer. Can you tell me what that mount looks like and which side it is on? I'll try to look it up. I know the fan comes on when it heats up though.
Ok. I checked the electric fan and it works. Along with overheating the heat stops working and blows cold air out also
sounds like the fan relay switch. To test it, start the car and turn your A/C on full crank, in about 2-5 minutes your fan should turn on.
Thank you. My husband and I decided to check the fluids on a whim and it turns out that the radiator when low on coolant. Since we added coolant we have no had any problems with our Jeep. The heat stays on and the car does not overheat or get close to it. The fluids will be the first thing I check from now on.
