What it means
A/C Compressor Motor Phase W Current Sensor Circuit High: the signal voltage is above the expected range. Often an open circuit or a short to supply voltage.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The phase W current sensor measures one electrical phase of the A/C compressor motor for the control module. This code sets when its circuit signal is higher than expected, commonly because the signal wire is open or shorted to a supply, or the sensor has failed.
Common causes
Most likely first.
- Current sensor failed
- Wiring fault
- Connector pins corroded - high contact resistance
Symptoms
- A/C warning light or check-engine light
- Air conditioning may cool poorly or stop cooling
How to diagnose it
- Record freeze-frame data and watch the phase W sensor reading on a scan tool to confirm the high signal and its operating conditions.
- Inspect the phase W connector and harness for a disconnected plug, broken wire, corrosion, or damage.
- Check for an open in the phase W signal circuit and a short to supply voltage using the manufacturer's wiring information.
- Check connector terminal condition and sensor power and ground as specified by the manufacturer.
- If the circuit checks out, test the phase W current sensor against the manufacturer's specification.
Common fixes
- Reconnect or secure a disconnected phase W sensor plug.
- Repair an open wire or short to supply in the phase W circuit.
- Repair corroded or damaged connector terminals.
- Replace the phase W current sensor if it fails testing.
Can I keep driving?
A/C cooling may stop because the control module cannot trust the phase W current reading and may disable the compressor. Driving is generally possible if no other warnings appear, but heed any hybrid or EV system alert.
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.