P0533

DTC P0532 or P0533

Circuit Description

The engine control module (ECM) monitors the high side refrigerant pressure through an A/C refrigerant pressure sensor. 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 A/C compressor clutch to engage.

DTC Descriptors

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.

Conditions for Setting the DTC

* A/C pressure of less than 0.3 volts or more than 4.92 volts.
* The condition must be present for more than 5 seconds.

Action Taken When the DTC Sets

* The ECM will not illuminate the malfunction indicator lamp (MIL).
* The ECM will store the conditions present when the DTC set as Fail Records data only.

Conditions for Clearing the DTC

* The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
* The DTC can be cleared by using the scan tool Clear DTC Information function.

Diagnostic Aids

Test the following conditions:

* Visually inspect the sensor for contamination or damage.
* Inspect for the following that may affect the sensors accuracy:

- A malfunction within the refrigerant system causing low pressure
- Visually inspect the A/C components and lines for damage.

* Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Test Description

Step 1 - Step 8:

Step 9 - Step 17:

The numbers below refer to the step numbers on the diagnostic table.
4. Tests for the proper operation of the circuit in the low voltage range.
5. Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
6. Tests for a short to voltage in the 5-volt reference circuit.
7. Tests for a high resistance or an open in the low reference circuit.