P0D76

What it means

P0D76 means the A/C compressor control module has found that the signal from its internal output driver temperature sensor is not plausible or does not behave as expected. The module compares the reported driver temperature with expected values, such as how it changes under load or compared with other temperature inputs, and it set the code when the two did not agree. How the module is fitted and which compressor it controls (typically an electrically driven unit) depends on the model, so check the manufacturer data for your vehicle.

Symptoms

• Air conditioning blows warm or works intermittently
• A/C compressor not engaging or cutting out unexpectedly
• A/C warning light or climate system fault message on the dash
• Reduced cooling performance, especially in hot weather
• Other A/C or hybrid system codes stored alongside it

Possible causes

• Fault in the A/C compressor control module (internal driver temperature sensor or electronics)likely
• Damaged, corroded or loose wiring or connectors between the control module and the vehicle network or power supplylikely
• Low or unstable supply voltage to the compressor module from a weak battery or poor earthpossible
• Compressor overheating due to excessive system load, such as over-pressure, restricted airflow or incorrect refrigerant chargepossible
• Insufficient cooling of the compressor module, where fitted with a cooling path or heat transfer arrangementpossible
• Outdated control module software that is a known cause on certain modelsrare

How to diagnose

1. Read all stored and pending codes, then note the freeze frame data, including ambient temperature, voltage and A/C status
2. Check the battery condition and charging voltage, and inspect the main power and earth connections to the compressor
3. Inspect the compressor module wiring, connectors and seals for damage, water ingress, corrosion or heat marking
4. Check for related A/C, communication or power supply codes and deal with those first
5. Check that the A/C system is operating normally: condenser airflow, cooling fan operation, refrigerant charge and system pressures
6. Using live data, watch the reported driver temperature against the ambient and compressor temperatures to see if it is stuck, drifting or implausible
7. Check the manufacturer data for any service bulletins or software updates for this fault on your model
8. Clear the code and test the A/C under load to see if the fault returns

How to fix

• Repair or replace damaged wiring, connectors or terminals, and secure the earth connections
• Correct a weak battery or charging system fault
• Fix any cooling or A/C system fault that overloads the compressor, such as a faulty fan, blocked condenser or incorrect refrigerant charge
• Replace the compressor or its control module if the internal sensor or electronics are faulty, following the manufacturer's procedure
• Update the control module software only where the manufacturer lists an update as the fix for this fault

Can I keep driving?

Nearby codes

• P0D75GenericA/C Compressor Control Module Output Driver Temperature Sensor Circuit
• P0D77GenericA/C Compressor Control Module Output Driver Temperature Sensor Circuit High