Where is the location of fan sensor on 2002 Chevy Trailblazer?

The 2002 Chevy Trailblazer doesn't have a single "fan sensor" in the way some vehicles might have a dedicated temperature sensor solely for the cooling fan. Instead, the cooling fan's operation is controlled indirectly through several components that communicate with the PCM (Powertrain Control Module). These include:

* Engine Coolant Temperature (ECT) Sensor: This sensor, located in the engine block, measures the coolant temperature. This is the primary input for the PCM to determine when to activate the cooling fan.

* PCM (Powertrain Control Module): The PCM receives the signal from the ECT sensor (and potentially other inputs like A/C request) and determines when the cooling fan needs to operate. It's the "brains" of the operation.

Therefore, there's no single point to check for a "fan sensor." Troubleshooting fan issues on a 2002 Trailblazer involves checking the ECT sensor, its wiring, the PCM, the fan relay, and the fan itself. A diagnostic scan tool is almost essential to accurately identify the problem.