DTC B2AEF or B2AF0-B2AF4
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. DTC Descriptor DTC B2AEF Air Conditioning Electrical Variable Displacement Compressor High Side Driver Circuit Low DTC B2AF0 Air Conditioning Electrical Variable Displacement Compressor High Side Driver Circuit High DTC B2AF1 Air Conditioning Electrical Variable Displacement Compressor Low Side Driver Circuit Low DTC B2AF2 Air Conditioning Electrical Variable Displacement Compressor Low Side Driver Circuit High DTC B2AF3 Air Conditioning Electrical Variable Displacement Compressor Circuit DTC B2AF4 Air Conditioning Electrical Variable Displacement Compressor Performance For symptom byte information, refer to Symptom Byte List. Diagnostic Fault Information
| Circuit Number | Circuit Function | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
| 7573 | B+ | B2AEF | B2AF3 | B2AF0 | — |
| 7574 | Control | B2AF1, B2AF4 | B2AF3 | B2AF2 | — |
Circuit/System Description This air conditioning system uses a conventional clutch to engage and mechanically turn the compressor and a variable displacement solenoid valve to alter the amount of displacement created by the turning of the compressor. The BCM provides both switched battery voltage and a pulse width modulated ground to the variable displacement solenoid valve. The BCM grounds the variable displacement solenoid using a (PWM) signal in order to control the amount of compressor displacement. The performance of the air conditioning compressor is based on adjusted interior temperature and engine load. Conditions for Running the DTC System voltage = 9 – 16 V BCM is awake and communicating The air conditioning compressor is operating Conditions for Setting the DTC Co d t o s o Sett g t e C B2AEF Circuit 7573 is shorted to ground B2AF0 Circuit 7573 is shorted to voltage B2AF1 Circuit 7574 is shorted to ground B2AF2 Circuit 7574 is shorted to voltage B2AF3 Circuit 7573 or circuit 7574 is open B2AF4 The BCM detects current on circuit 7574 when the driver is commanded off Action Taken When the DTC Sets The air conditioning compressor solenoid operation is disabled. The A/C request is switched OFF. Output will be switched off for hardware protection. DTC Type C Conditions for Clearing the DTC DTC Type C Reference Information Schematic Reference HVAC Schematics Connector End View Reference Master Electrical Component List Description and Operation Automatic HVAC Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs DTC Type reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions Scan Tool Reference Control Module References for scan tool information Circuit/System Testing
- Ignition OFF and all vehicle systems OFF, disconnect the connector at the Q46 Air Conditioning Compressor Solenoid Valve. Connect a test light between terminals 1 and 2 of the connector. Ignition ON/ Vehicle in Service Mode.
- Verify the test light turns on and off when commanding the Q46 Air Conditioning Compressor Solenoid Valve ON and OFF with the scan tool. ⇒ If the test light does not turn ON and OFF 2.1. Ignition/ Vehicle OFF, disconnect the X5 connector at the K9 Body Control Module, Ignition ON/ Vehicle in Service Mode. 2.2. Test the circuits listed below for a short to voltage: Circuit 7573 Circuit 7574 ⇒ If a short to voltage is found, repair the fault on the circuit. ⇓ If a short to voltage is not found 2.3. Ignition/ Vehicle OFF. 2.4. Test the circuits listed below for a short to ground: Circuit 7573 Circuit 7574 ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 2.5. Test the circuits listed below for an open/high resistance: Circuit 7573 Circuit 7574 ⇒ If an open/high resistance is found, repair the fault on the circuit. ⇓ If an open/high resistance is not found Replace the K9 Body Control Module ⇓ If the test light turns ON and OFF
- Test the Q46 Air Conditioning Compressor Solenoid Valve or replace the G1 Air Conditioning Compressor. Component Testing Q46 Air Conditioning Compressor Solenoid Valve
- Ignition OFF and all vehicle systems OFF, disconnect the connector at the Q46 Air Conditioning Compressor Solenoid Valve.
- Test for 7–15 Ω between B+ terminal 2 and control terminal 1 at the Q46 Air Conditioning Compressor Solenoid Valve. ⇒ If less than 7 Ω or greater than 15 Ω Replace the G1 Air Conditioning Compressor. ⇓ If between 7–15 Ω
- Test for infinite resistance between each terminal and the Q46 Air Conditioning Compressor Solenoid Valve housing/case. ⇒ If less than infinite resistance Replace the G1 Air Conditioning Compressor. ⇓ If infinite resistance
- All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. HVAC Component Replacement Reference Control Module References for control module replacement, programming and setup