P0533 A/C Refrigerant Pressure Sensor A Circuit High

Definition: The OBD2 code P0533 indicates that the powertrain control module (PCM) has detected a high voltage condition in the air conditioning (A/C) refrigerant pressure sensor circuit. This typically means that the sensor is reporting a pressure level that is higher than expected.

p0533 – A/C Refrigerant Pressure Sensor A Circuit High

Typical Severity: Moderate

Common Causes

P0533 – A/C Refrigerant Pressure Sensor A Circuit High

Common causes include:

• Faulty A/C refrigerant pressure sensor
• Short circuit in the wiring of the A/C refrigerant pressure sensor
• Open circuit in the wiring of the A/C refrigerant pressure sensor
• Low refrigerant level in the A/C system
• Faulty air conditioning compressor
• Faulty ECM/PCM (engine control module/powertrain control module)

 

Common Misdiagnosis

OBD2 Code: P0533

Description: A/C Refrigerant Pressure Sensor A Circuit High

Common Misdiagnosis: Replacing the refrigerant pressure sensor without checking for wiring issues or verifying that the system is not overcharged with refrigerant.

 

Common Diagnostic Steps

OBD2 Code: P0533

Description: A/C Refrigerant Pressure Sensor A Circuit High

• Verify the code with an OBD-II scanner and clear it to see if it returns.
• Inspect the refrigerant pressure sensor and its wiring for any visible damage or corrosion.
• Check the electrical connections at the sensor for tightness and cleanliness.
• Measure the voltage at the sensor connector using a multimeter to ensure it’s within specifications.
• If applicable, check for proper refrigerant levels in the A/C system.
• Test the continuity of wires between the sensor and ECM (Engine Control Module).
• If all checks are normal, consider replacing the refrigerant pressure sensor.
• If issues persist after replacement, further diagnose potential ECM faults or software updates needed.