Cooling Fan Always On

Cooling Fan Always On (1.8L RPO-LAY)

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 fan 1 relay provides power to the fan control module. The fan control module completes the fan motor circuit by providing a path to ground. The module energizes the fan and controls fan speed according to instructions received from the powertrain control module (PCM).

Reference Information
Schematic Reference

Engine Cooling Schematics (Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Cooling Fan Description and Operation (Cooling Fan Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

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

Circuit/System Verification

1. Verify the HVAC system operates correctly.

• If an HVAC system condition is found, repair the HVAC condition first. Refer to Symptoms - HVAC Systems - Manual (Symptoms - HVAC Systems - Manual).

2. Ignition ON, observe that the fan is not activated.

• If the fan is activated, test the fan control module circuit terminal 2 for an open/high resistance. If the circuit tests normal, replace the PCM.

Repair Instructions

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

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