The Location of a Cadillac Fan Sensorby Marion Cobretti
The fan sensor, or cooling fan control switch by its more popular name, controls the operation of your Cadillac's radiator fan. When the coolant within the radiator reaches a specified temperature, the sensor activates the fan. Your Cadillac actually has two cooling fan control switches. Depending on the model Cadillac you have, the radiator has either a dual-speed fan or two separate fans. One of the cooling fan control switches reacts to lower temperatures and the other to higher temperatures. You can find and replace one or both fan sensors; removing either of them will require draining the coolant.
Raise the hood on your Cadillac and locate the radiator. Your Cadillac's radiator mounts within the engine compartment. If you peer down at the front of the engine compartment just beyond the bumper, you will see the radiator. It has black, rubber hoses hooked up to it and your cooling fan mounts directly against it.
Move over and stand on the driver's side of the radiator. Locate your Cadillac's cooling fan control switches on the inner side of the radiator. Both switches have a wiring harness plugged into their tops. The first switch mounts 3 inches from the top of the radiator. The second cooling fan control switch mounts just above the lower radiator hose 8 inches from the bottom of the radiator.
Remove either cooling fan control switch from your Cadillac by first disconnecting the battery's negative cable. Remove the radiator cap and drain the coolant into a suitable drain pan. Unplug the wiring harness from the switch that you're replacing. Unscrew the cooling fan control switch from the radiator with a socket wrench.
- Reuse the coolant that you drain from the radiator only if your Cadillac has recently had its cooling system flushed. Otherwise, refill the radiator with fresh coolant. If one cooling fan switch has failed, it's more than likely the other one will do so soon. You can avoid performing this repair again by replacing both switches during one setting.