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 the diagnostic category.
DTC Descriptors
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.
Conditions for Running the DTC
* Engine is running.
* Any of the conditions for setting the DTC are met for 15 seconds.
* Battery voltage is between 11-18 V.
Conditions for Setting the DTC
* The ECM detects that the A/C pressure is less than 1 psi (0.01 V).
* The ECM detects that the A/C pressure is more than 428 psi (4.92 V).
Action Taken When the DTC Sets
This is a type D DTC.
Conditions for Clearing the DTC
This is a type D DTC.
Diagnostic Aids
A malfunction within the refrigerant system causing high pressure can cause this DTC to set.
Reference Information
Schematic Reference
HVAC Schematics HVAC - Automatic
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
Automatic HVAC Description and Operation 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
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
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 in the ECM data list. The reading should be between 6.8 kPa (1 psi) and 2950 kPa (428 psi).
Circuit/System Testing
1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B1 A/C refrigerant pressure sensor. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal 1 and ground.
• If 10 ohms or greater
1. Ignition OFF, disconnect the X1 harness connector at the K20 ECM.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 ECM.
• If less than 10 ohms
3. Ignition ON.
4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 2 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the X1 harness connector at the K20 ECM.
2. Test for infinite resistance between the 5 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the 5 V reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 ECM.
• If greater than 5.2 V
1. Ignition OFF, disconnect the X1 harness connector at the K20 ECM, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 ECM.
• If between 4.8-5.2 V
5. Verify the scan tool engine control module A/C High Side Pressure Sensor parameter is less than.25 V.
• If.25 V or greater
1. Ignition OFF, disconnect the X1 harness connector at the K20 ECM, ignition ON.
2. Test for less than 1 V between the signal circuit terminal 3 and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 ECM.
• If less than.25 V
6. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 2.
7. Verify the scan tool engine control module A/C High Side Pressure Sensor parameter is greater than 4.8 V.
• If 4.8 V or less
1. Ignition OFF, disconnect the X1 harness connector at the K20 ECM.
2. Test for infinite resistance between the signal circuit terminal 3 and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 ECM.
• If greater than 4.8 V
8. Test or replace the B1 A/C refrigerant pressure sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* HVAC Component Replacement Reference HVAC Component Replacement Reference
* Control Module References Programming and Relearning for ECM replacement, programming and setup