Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Stepper Motors 12 V Reference | B023A 02, B0223 06, B0233 06, B0408 06 | B0223 06, B0233 06, B0408 06 | -- | -- |
Recirculation Actuator Control 1 | B0223 06 | B0223 06 | B0223 01 | 1 |
Recirculation Actuator Control 2 | B0223 06 | B0223 06 | B0223 01 | 1 |
Recirculation Actuator Control 3 | B0223 06 | B0223 06 | B0223 01 | 1 |
Recirculation Actuator Control 4 | B0223 06 | B0223 06 | B0223 01 | 1 |
1. Air Recirculation Malfunction | ||||
Circuit/System Description
The desired position of the recirculation flap can be set with the recirculation switch at the HVAC control,. The selected value is sent to the HVAC control module via the LIN-Bus. The HVAC control module supplies a 12 V reference voltage to the stepper motor and energizes the 4 stepper motor coils with a pulsed ground signal. The stepper motor moves the recirculation flap into the selected position.
Diagnostic Aids
Check the following mechanical fault sources:
| • | Air distribution box |
| • | Air distribution hoses/air distribution ducts |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Manual HVAC Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition ON, press and release the defrost switch. Verify the scan tool Enhanced Defrost Switch parameter changes between Active and Inactive.
- Press and release the recirculation switch. Verify the scan tool Air Recirculation Mode Switch parameter changes between Active and Inactive.
- If all circuits test normal, replace the M46 Recirculation Actuator and verify the M46 Recirculation Actuator can be activated and deactivated. If the M46 Recirculation Actuator cannot be activated or deactivated, replace the K33 HVAC Control Module.
| ⇒ | If not the specified value, replace the A26 HVAC Control. |
| ⇒ | If not the specified value, replace the A26 HVAC Control. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
