What it means
The ECM detects a circuit fault on the a/c compressor motor voltage sensor b circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Voltage sensor B monitors an electrical voltage signal from the A/C compressor motor for the control module. P0EAA indicates a general fault in the sensor B circuit, so the module cannot rely on that signal; this code does not by itself identify a low, high, or out-of-range reading.
Common causes
Most likely first.
- Sensor failed
- Wiring or connector fault
Symptoms
- Check-engine or hybrid system warning light
- Air conditioning may not cool
- Cooling may be intermittent
How to diagnose it
- Read freeze-frame data and all related hybrid and A/C codes to see when the sensor B circuit fault occurred and whether other compressor faults are present.
- Inspect the voltage sensor B connector and harness for loose seating, corrosion, damaged insulation, or pulled wires.
- Check the sensor B circuit's power or reference, ground, and signal connections using the manufacturer's wiring information.
- Test the sensor B wiring for opens, shorts, and excessive resistance, with the system made safe according to manufacturer instructions.
- If the wiring and connections pass, compare sensor B operation with the manufacturer's specification to determine whether the sensor has failed.
Common fixes
- Reconnect the sensor B plug securely and clean or repair corroded terminals.
- Repair an open, shorted, or damaged wire in the sensor B circuit.
- Restore a poor sensor ground or reference connection.
- Replace voltage sensor B if its circuit checks pass but its signal does not meet specification.
Can I keep driving?
The A/C may stop cooling and the vehicle may display a hybrid system warning; follow any vehicle warning to stop or limit operation. If there are no stop-driving warnings or other drivability symptoms, avoid relying on the A/C and arrange diagnosis soon.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.