Q: 2015 Jeep Renegade with check engine light for thermostat. Car is not overheating and has coolant. What could be the issue?

asked by on December 04, 2017

Saturday morning I took my car into the dealership for an oil change. Sunday morning the check engine light came on. Took the car to AutoZone where they scanned the computer and it showed that there is an issue with the thermostat. The dealership did a vehicle check and showed that the coolant marked as a yellow (out of a red, yellow, green light scale). I checked the coolant myself and it is almost full. The car has not been overheating. I am very wary of the dealership trying to get unnecessary money out of me and don't know a reputable mechanic. What should I do?

My car has 26000 miles.
My car has an automatic transmission.

Depending on the code you got for the cooling system it may indicate the thermostat did not open in the normal time when it was supposed to open and the computer will set a code for this. The thermostat will degrade over time and may even stick closed and will start to cause an overheat problem. I would recommend replace the thermostat and coolant as indicated by codes to help prevent an engine overheating that could cause engine damage if ignored.

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