P2D29: A/C Compressor Motor Stalled

What it means

The electric A/C compressor motor is stalled. High mechanical resistance, internal seizure, or refrigerant overpressure prevents rotation.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

The electric A/C compressor motor turns the compressor to circulate refrigerant and cool the cabin. P2D29 sets when the motor is commanded to run but stalls, typically because the compressor has high mechanical resistance or refrigerant pressure is high enough to prevent rotation.

Common causes

Most likely first.

1. Compressor mechanically seized
2. Refrigerant overpressure stalls compressor

Symptoms

• Check-engine or A/C warning
• A/C blows warm air
• A/C operation may be unavailable

How to diagnose it

1. Use a scan tool to review freeze-frame data and A/C compressor command and status when the stall was recorded.
2. Check whether the A/C warning is present and whether the system produces warm air when cooling is requested.
3. With the vehicle powered down as specified by the manufacturer, inspect the compressor connector and visible wiring for damage or loose connections.
4. Have refrigerant pressures and system operation checked using the manufacturer's procedure to identify overpressure or another system restriction.
5. If pressure and wiring checks are satisfactory, test the electric compressor motor and compressor for mechanical seizure according to the manufacturer's procedure.

Common fixes

• Repair a loose or damaged compressor electrical connection.
• Correct a refrigerant-system fault causing excessive pressure, following the manufacturer's service procedure.
• Replace the compressor if it is mechanically seized or its motor fails testing.
• Clear the code and verify the compressor runs and cools normally.

Can I keep driving?

The vehicle can generally be driven without A/C if it runs normally, but expect warm air and possible power limitation. Do not keep requesting A/C if the compressor stalls repeatedly; stop if a separate vehicle warning or loss of propulsion occurs.