Engine Coolant Temperature Gauge Inaccurate or Inoperative

Engine Coolant Temperature Gauge Inaccurate or Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

Circuit/System Description

The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the engine control module (ECM). The ECM sends the temperature data via the serial data circuit to the IPC in order to display the engine temperature.

Reference Information
Schematic Reference

Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

* Instrument Cluster Description and Operation (Instrument Cluster)
* Cooling System Description and Operation (Cooling System Description and Operation)

Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, perform the engine coolant gauge sweep test with the scan tool. Verify that the engine coolant temperature gauge sweeps from its low to high position.

If the engine coolant gauge does not sweep from its low to high position, replace the IPC.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for IPC replacement, setup, and programming