Coolant Level Sensor: Testing and Inspection

Chart C-16:

Chart C-16 Wiring Diagram:

CIRCUIT DESCRIPTION:


The TEMP light is connected to battery voltage through the ignition switch. The ECM illuminates the bulb by supplying a path to ground through quad-driver module #2.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. With the ignition "ON" and engine "OFF," the ECM should be grounding circuit 35.

2. The TEMP light should only be controlled to be turned "ON" while the engine is running when the coolant temperature is above 123~C (253~F).

DIAGNOSTIC AIDS

The coolant temperature sensor, in rare cases, may fail to indicate the correct engine coolant temperature without setting a malfunction code. This could result in turning "ON" the TEMP light without having a overheating condition.