When i start my truck, sometimes my radiator fan comes on full blast immediately. After about thirty seconds it'll go to normal speed. Also while driving it will come on full blast periodically. The truck isn't running hot and it even does it during cold temperatures on my first start for the day. I was thinking maybe my water pump and thermostat need changing, but i have/never have a check engine light or any other warning on the dashboard.
My car has 95000 miles.
My car has an automatic transmission.
The fan circuit has a relay, switch contacts, and a temperature sensor. There may be other circuit components as well. If the fan is coming on when it is not supposed to, there is a fault in one or more of those components or perhaps an intermittent short to ground in the circuit. Basically, if you want to resolve it yourself, using the wiring diagram (from the Factory Service Manual, FSM) you can methodically trace the circuit until the fault(s) is found. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an electrical component diagnostic - uncommanded fan operation and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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