[Dirty Bird 07]

I'm new here, I replaced the coolant temp sensor and the thermostat in my 07 3.5l. The heat works ok, not as hot as it was, and the temp gauge doesn't move and the fans come on full throttle when I start the car. Any ideas what else it could be? I'd really appreciate it

 

[mrslcom]

Is there an engine code? Most likely a faulty thermostat.

 

[Dirty Bird 07]

I replaced the thermostat as well as the coolant temperature sensor. Still no temperature reading on the gauge, and fans come on as soon as the engine is started

 

[mrslcom]

If one of those two parts fail the system will default in safe mode which means fans on and temperature gauge disabled.

 

[boomer]

I would expect the temperature sensor is a thermistor. If you have access to a multimeter, you could measure the resistance across the pins. If you can get hold of a resistor like 100 - 150 Ohm you could also try putting it across the connector pins to simulate the operating temperature. Should give you a clue to the condition of the sensor, wiring, etc. From another schematic, Low Reference looks to be the same as battery / chassis ground so it may be possible to check for continuity.

Hope some of this helps.

 

[Darksiedforu]

I'm new here, I replaced the coolant temp sensor and the thermostat in my 07 3.5l. The heat works ok, not as hot as it was, and the temp gauge doesn't move and the fans come on full throttle when I start the car. Any ideas what else it could be? I'd really appreciate it

Check your thermostat. I had a similar problem like that before. Only difference is the temp gauge would raise up to first notch then drop back to zero. Ac wouldn't work either. I would have to unhook battery again just to get the correct reading an AC to work again. I replaced the coolant temp sensor. Didn't fix it. Then went to replace the thermostat an come to find out who ever own the vehicle before me too the thermostat is out an didn't put another one in. Once I put in the new thermostat it ran the way it should have. Still don't know why they took the thermostat out in the first place.