P0EAF

Code

Generic P — Powertrain

A/C Compressor Motor Current Sensor Circuit Low

Brand: Generic

Type: P — Powertrain

Views: UK: 29 EN: 36 RU: 24

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Page language: EN

Causes

Open or shorted wiring in the compressor current sensor circuit
Low or lost reference power or ground to the sensor or its controller
Faulty A/C compressor motor current sensor (Hall-effect or shunt type)
Faulty A/C inverter / compressor drive module
Faulty A/C compressor motor (high internal resistance or winding fault)
Corroded or loose connector pins at sensor, inverter or PCM

Symptoms

A/C compressor may not engage or may shut off intermittently
Reduced or no air conditioning cooling
DTC P0EAF stored and MIL or HVAC warning lamp may be illuminated
Unusual inverter/compressor behavior (soft-start, repeated cycling)
Possible increased cabin blower runtime with no cooling

What to check

Read and record freeze-frame and live data for compressor current and related parameters
Confirm whether the compressor is commanded ON by the HVAC/PCM
Visually inspect wiring and connectors from current sensor to inverter and to PCM for damage or corrosion
Check fuses and relays for the compressor and inverter power circuits
Measure sensor connector voltages and ground with key on / compressor commanded
Use a clamp ammeter on compressor motor feed (if accessible) to verify actual current when commanded

Signal parameters

Typical sensor signal: 0–5.0 V analog (varies by design); low-fault when signal is near 0.0–0.5 V
Some sensors output a centered voltage (e.g., ~2.5 V) with ± change as current flows; a persistent low (
Expected compressor running current (typical small vehicle): roughly 5–50 A depending on system; verify manufacturer spec
Supply/reference voltage to sensor: usually stable 5 V or vehicle battery voltage; ground continuity should be
Communication bus (if sensor reports via CAN or LIN) should show normal bus voltages and no bus errors

Diagnostic algorithm

Retrieve DTCs and freeze-frame data. Note compressor command state, measured current, and vehicle conditions.
Verify basic power and grounds: check fuse(s) and relay for compressor/inverter. Repair any open circuits before proceeding.
With the key ON and HVAC commanding compressor, monitor the live current-sensor signal and compare to expected values. Record behavior when compressor is commanded ON and OFF.
Visually inspect the sensor, connector, and wiring harness for physical damage, pin corrosion, water intrusion, or chafing. Wiggle test while monitoring live data to check intermittent faults.
Measure sensor connector voltages: reference/supply, signal, and ground. If signal is low with correct supply and ground, suspect sensor or short to ground.
If the sensor is a shunt or Hall-effect packaged at the inverter/compressor, check inverter ground and chassis ground points. Repair any poor grounds.
If wiring checks are good, unplug the sensor and inspect pins. If allowed by manufacturer, substitute a known-good sensor or perform bench test per service literature.
Measure actual compressor motor current with a clamp meter while commanded. If motor current is zero or abnormally low and sensor reads low, confirm motor/inverter functionality.
If inverter/drive suspected, consult manufacturer procedures for inverter diagnosis; check for other inverter codes and inspect high-voltage interlocks (on hybrid/electric vehicles) before further testing.
After repair, clear codes and perform a test drive or A/C function test to confirm the code does not return and that system cooling is restored.