Operation CHARM: Car repair manuals for everyone.

Hot Indicator

The HOT Indicator lights to warn of overheating when the Engine Coolant Temperature (ECT) sensor closes. The Powertrain Control Module (PCM) controls this indicator. When the PCM senses an over-temperature condition, it grounds the HOT indicator. When the ignition switch is in RUN with the engine off, the HOT indicator is grounded by the PCM as a bulb test.