Air Recirculation Malfunction

Air Recirculation Malfunction

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.

Diagnostic Fault Information





Circuit/System Description

The recirculation actuator is a 2-wire bi-directional electric motor. There are 2 control circuits that enable the actuator to operate. The control circuits use either a 0 or 12-volt value to coordinate the actuator movement. When the actuator is at rest, both control circuits have a value of 0 volts. In order to move the actuator, the HVAC control module grounds one of the control circuits while providing the other with 12 volts. The HVAC control module reverses the polarity of the control circuits to move the actuator in the opposite direction.

Reference Information
Schematic Reference

HVAC Schematics (HVAC - Manual)
Connector End View Reference

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

* Air Temperature Description and Operation (Air Temperature)
* Air Delivery Description and Operation (Air Delivery)

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

Ignition ON, observe the operation of the drive shaft of the recirculation actuator while using the recirculation control switch. The drive shaft of the recirculation actuator should rotate.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the recirculation actuator.
2. Ignition ON, connect a test lamp between the control circuit terminal A and control circuit terminal B. Command the actuator in each direction. The test lamp should illuminate when commanding the actuator in one direction to the other direction.

• If the test lamp is always OFF, test the appropriate control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the HVAC control module.
• If the test lamp is always ON, test the appropriate control circuit for a short to voltage. If the circuit tests normal, replace the HVAC control module.

3. If all circuits test normal, test or replace the recirculation actuator.

Component Testing

1. Install a 10-amp fused jumper wire between the control terminal A and 12 volts. Momentarily install a jumper wire between the control terminal B and ground. The recirculation actuator shaft should rotate.

• If the function does not perform as specified, replace the recirculation actuator.

2. Reverse the jumper wires, the recirculation actuator shaft should rotate.

• If the function does not perform as specified, replace the recirculation actuator.

Repair Instructions

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

* Air Inlet Valve Actuator Replacement (Air Inlet Valve Actuator Replacement)
* Control Module References (Programming and Relearning) for HVAC replacement, setup, and programming