A short to ground in the sensor B signal wire or connector.; A failed A/C compressor motor voltage sensor B.; Internal short in the electric A/C compressor motor.; Corroded or damaged wiring harness at the compressor connector.; A faulty powertrain control module driver for the sensor circuit.; Low refrigerant charge causing the compressor to overheat and distort sensor readings.

DTC codes / P0Exx · Hybrid propulsion / P0EAC

P0EACA/C Compressor Motor Voltage Sensor B Circuit Low

Q: What does code P0EAC mean?

A/C Compressor Motor Voltage Sensor B Circuit Low. P0EAC indicates that the powertrain control module has detected a low voltage condition on the signal circuit for the air conditioning compressor motor voltage sensor B. This sensor monitors the high-voltage motor inside the electric A/C compressor, and a low signal typically means the circuit is shorted to ground, the sensor has failed, or the compressor motor is drawing abnormal current.

P0EAC indicates that the powertrain control module has detected a low voltage condition on the signal circuit for the air conditioning compressor motor voltage sensor B. This sensor monitors the high-voltage motor inside the electric A/C compressor, and a low signal typically means the circuit is shorted to ground, the sensor has failed, or the compressor motor is drawing abnormal current.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaHybrid propulsion

Symptoms you may notice

The air conditioning may blow warm air or not engage at all.
The climate control panel may show a fault or flash the A/C indicator.
The engine may idle roughly or surge when the A/C is turned on.
A noticeable drop in fuel economy if the compressor clutch cycles erratically.
Often no symptoms besides the warning light, especially if the fault is intermittent.

Common causes, most likely first

A short to ground in the sensor B signal wire or connector.
A failed A/C compressor motor voltage sensor B.
Internal short in the electric A/C compressor motor.
Corroded or damaged wiring harness at the compressor connector.
A faulty powertrain control module driver for the sensor circuit.
Low refrigerant charge causing the compressor to overheat and distort sensor readings.

How to diagnose and fix it

Scan all modules for stored codes and freeze-frame data to confirm P0EAC is active.
Inspect the compressor motor voltage sensor B connector and wiring for chafing, corrosion, or loose pins.
Measure resistance from the sensor B signal wire to ground to check for a short.
Back-probe the sensor B signal circuit with a multimeter and compare voltage to the service specification.
Test the A/C compressor motor for excessive current draw or internal short using a clamp meter.
If the circuit and sensor test good, substitute a known-good sensor B and clear codes to see if the fault returns.
Repair or replace the faulty wiring, sensor, or compressor as indicated by the test results, then verify the repair with a road test.

Before you replace the A/C compressor

A low voltage code on sensor B is frequently caused by a rubbed-through signal wire near the compressor clutch or engine mount, not by the sensor itself.
Technicians often replace the compressor only to find the same code returns because the connector terminals were spread and making poor contact.
This code can set intermittently when the A/C is turned off during deceleration, so always check for pending codes and freeze-frame data before condemning parts.
A weak battery or charging system voltage drop can cause the module to misread the sensor signal as low, so verify system voltage first.
On some vehicles, the compressor motor voltage sensor is integrated into the compressor and cannot be serviced separately, making circuit testing even more critical.

Can I keep driving with P0EAC?

You can usually drive the vehicle with this code, but the air conditioning may not work and prolonged driving with a shorted sensor circuit could damage the compressor or control module. Avoid using the A/C until the fault is diagnosed, and have the circuit tested promptly.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.