P0533

DTC P0532 or P0533

Circuit Description

The engine control module (ECM) or powertrain control module (PCM) monitors the high side refrigerant pressure through the A/C refrigerant pressure sensor. The ECM or PCM supplies a 5-volt reference and a low reference to the sensor. Changes in the A/C refrigerant pressure cause the A/C refrigerant pressure sensor signal to the ECM or PCM 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 or PCM commands the cooling fans ON. When pressure is too high or too low, the ECM or PCM will not allow the A/C compressor clutch to engage.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

* DTC P0532 (A/C) Air Conditioning Pressure Sensor Circuit Low Voltage
* DTC P0533 (A/C) Air Conditioning Pressure Sensor Circuit High Voltage

Conditions for Running the DTC

* The engine is running.
* Any of the conditions for setting the DTC are met for 15 seconds.

Conditions for Setting the DTC

* The ECM or PCM detects that the A/C pressure is less than 34Kpa or 4.93 psi (0.25 volt).
* The ECM or PCM detects that the A/C pressure is more than 3339Kpa or 484 psi (4.75 volts).

Action Taken When the DTC Sets

* The ECM or PCM will not illuminate the malfunction indicator lamp (MIL).
* The ECM or PCM stores the Failure Records.
* The A/C compressor clutch is disabled.

Conditions for Clearing the DTC

* The history DTC will clear after 40 consecutive ignition cycles have occurred without a malfunction.
* The DTC can be cleared by using the scan tool.
* The DTC will become history if the ECM or PCM no longer detects a failure.

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 high 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. This step tests for the proper operation of the circuit in the low voltage range.
5. This step 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. This step tests for a short to voltage in the 5-volt reference circuit.
7. This step tests for a high resistance or an open in the low reference circuit.