Circuit Description

The coolant temperature gauge is directly controlled by the PCM using a Pulse Width Modulated (PWM) signal, based on information from the Engine Coolant Temperature (ECT) sensor. The PCM uses the inputs from the ECT to control fuel, A/C cooling fan and LOW COOLANT/HOT lights. The ECT is the only coolant temperature sensing device on both the DOHC and SOHC engines.

DTC will set if there is an open, short to ground or short to voltage in the coolant gauge circuit. Coolant gauge circuit is continuously checked when ignition is on.