P0533

DTC P0532 or P0533

Circuit Description

The air conditioning (A/C) refrigerant pressure sensor is used by the engine control module (ECM) to monitor the high side refrigerant pressure. The A/C refrigerant pressure sensor utilizes the following 3 circuits:

* A 5-volt reference circuit

* A low reference circuit

* A signal circuit

The ECM monitors the signal circuit voltage. If the A/C high side pressure is high, the signal voltage is high. If the A/C high side pressure is low, the signal voltage is low. The ECM uses the voltage readings to determine the operation of the A/C compressor and the cooling fans. If the ECM detects an excessively high or low signal voltage, a DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTCs:

* DTC P0532 Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit Low Voltage

* DTC P0533 Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit High Voltage

Conditions for Running the DTC

* The engine is running.

* The A/C is requested.

* DTC P0532 and P0533 run continuously once the above condition is met.

Conditions for Setting the DTC

P0532

* The ECM detects that the A/C pressure is less than 0.1 volt.

* The condition exists for more than 10 seconds.

P0533

* The ECM detects that the A/C pressure is more than 4.9 volts.

* The condition exists for more than 10 seconds.

Action Taken When the DTC Sets

* The control module stores the DTC information into memory when the diagnostic runs and fails.

* The malfunction indicator lamp (MIL) will not illuminate.

* The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.

* The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC

* A current DTC Last Test Failed clears when the diagnostic runs and passes.

* A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.

* Clear the DTC with a scan tool.

Diagnostic Aids

* For HVAC system concerns, refer to HVAC Preliminary Checks HVAC Preliminary Checks in Heating, Ventilation and Air Conditioning.

* For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections in Wiring Systems.