P0D72

What it means

P0D72 means the A/C compressor control module has detected that the signal from its own internal temperature sensor 'A' is higher than the expected range. The module is usually part of an electric or hybrid-style compressor. It sets the code when the sensor reading stays at or beyond the top of its range, which points to a sensor fault, a circuit fault or a genuine overheat condition inside the module.

Symptoms

• A/C blows warm or does not work at all
• A/C compressor does not start or cuts out soon after starting
• Warning light on the dashboard, such as a general or hybrid system warning on some models
• Reduced or erratic cooling performance in hot weather
• Other A/C or compressor communication codes stored alongside it

Possible causes

• Fault inside the compressor control module, such as a failed internal temperature sensorlikely
• Corroded, loose or damaged compressor connector or terminalspossible
• Genuine overheating of the module from low refrigerant, a restricted system or a worn compressorpossible
• Low or unstable 12 V supply, or a poor earth to the compressor modulepossible
• Damaged wiring or communication fault between the module and the vehicle networkpossible
• Outdated or faulty control module calibration, where the manufacturer has identified this as a known issuerare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting ambient temperature, vehicle speed and A/C status when the code set
2. Check for related A/C, network communication or supply voltage codes and deal with those first
3. Inspect the compressor connector and wiring for corrosion, water ingress, heat damage, chafing and bent or pushed-back terminals
4. Check the 12 V battery condition and the supply and earth to the compressor module under load
5. With the car cold, compare the module's reported internal temperature with ambient temperature using live data; an implausibly high fixed value suggests a sensor or module fault
6. Check A/C refrigerant charge, system pressures and compressor cooling or airflow, as overheating can be real rather than a sensor fault
7. Check for manufacturer service information on calibration updates or known faults for this model
8. Only trained technicians should work on high-voltage compressors, following the correct isolation procedure

How to fix

• Repair or replace damaged wiring, connectors or terminals, and clean off any corrosion
• Restore a stable 12 V supply and good earth connections, including battery replacement if it is weak
• Correct any A/C system fault causing overheating, such as incorrect refrigerant charge or a restriction
• Replace the compressor or control module if the internal sensor is faulty; whether the module is supplied separately depends on the model
• Apply a calibration update only if the manufacturer lists it as the fix for this fault
• Clear the code and road test with the A/C running to confirm it does not return

Can I keep driving?

Nearby codes

• P0D71GenericA/C Compressor Control Module Internal Temperature Sensor A Performance
• P0D73GenericA/C Compressor Control Module Internal Temperature Sensor A Circuit Low