P0532
DTC P0532 or P0533
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.
DTC Descriptor
DTC P0532
- Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit Low Voltage
DTC P0533
- Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) monitors the high side refrigerant pressure through the A/C refrigerant pressure sensor. The ECM supplies a 5 V reference and a low reference to the sensor. Changes in the A/C refrigerant pressure cause the sensor signal to the ECM to vary. When the pressure is high, the signal voltage is high. When the pressure is low, the signal voltage is low. When pressure is high, the ECM commands the cooling fans on. When pressure is too high or too low, the ECM will not allow the activation of the A/C compressor.
Conditions for Running the DTC
Engine is running.
Conditions for Setting the DTC
P0532
The ECM detects a short to ground or open at the A/C pressure sensor signal circuit.
P0533
The ECM detects a short to voltage at the A/C pressure sensor signal circuit.
Action Taken When the DTC Sets
* The A/C compressor is disabled.
* The ECM will illuminate the malfunction indicator lamp (MIL).
Conditions for Clearing the DTC
The condition for setting the DTC is no longer present.
Reference Information
Schematic Reference
HVAC Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Manual HVAC Description and Operation (HVAC - Manual)
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 scan tool A/C High Side Pressure Sensor parameter. The reading should be between 0.1 V (1 PSI) and 4.90 V (425 PSI) and change with A/C refrigerant pressure changes.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B1 A/C Refrigerant Pressure Sensor.
2. Test for less than 5 ohm between the low reference circuit terminal 1 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 2 and ground.
• If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace K20 Engine Control Module.
• If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
4. Verify the scan tool A/C High Side Pressure Sensor parameter is less than 0.1 V (1 PSI).
• If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 2. Verify the scan tool A/C High Side Pressure Sensor parameter is greater than 4.9 V (425 PSI).
• If less than the specified range, test the signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
6. If all circuits test normal, replace the B1 A/C Refrigerant Pressure Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for engine control module replacement, setup, and programming