Q: replaced the engine temp sensor and now the cooling fans wont turn on

asked by on October 25, 2016

The engine temperature sensor was replaced and now the cooling fans will not turn on automatically when the engine gets hot. The fans work as when the air con is turned on they kick on. The old sensor did not have this issue and the engine would run at a stable temperature.

My car has 125000 miles.
My car has a manual transmission.

Hello there, a few common faults will cause your cooling fans to not work after the temperature sensor was replaced on your 2003 Subaru Impreza. If the problems started right after the repair was made the replacement coolant temperature sensor may be faulty, this would be unusual but it is possible. Other potential faults are the cooling fans themselves, fan relay, wiring harness fault or the ECU. A Qualified Technician such as one from YourMechanic will be able to diagnose your cooling fan issues and make any repairs required to resolve them.

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