Circuit Description

WARNING: This page is about a different car, the 2000 Isuzu Rodeo and 2000 Isuzu Amigo. However, it is still accessible from the selected car via links, so may be relevant.

Engine Coolant Temperature (ECT) sensor is a thermistor that varies resistance based on temperature. As temperature of ECT sensor increases, resistance decreases. High temperature will result in a low signal voltage. ECT sensor value will be about 1.5-2.0 volts when engine is fully warmed.

Conditions required to set DTC are:

Engine running for longer than two minutes.
ECT sensor signal indicates 302°F (150°C), about .14 volts for 12 seconds, over a 25-second period.