What it means
The proximity detection circuit B (SAE J1772 PD signal) reports a range/performance condition. Charging cable plug detection is impaired.
At a glance
- Usually lights the check-engine light
How it works
Proximity detection circuit B carries the SAE J1772 signal used to detect the charging plug at the inlet. The control module checks whether the signal falls within its expected operating range; this code sets when circuit B's reading is outside that range or does not respond as expected, rather than simply being persistently low.
Common causes
Most likely first.
- Charge inlet contacts dirty
- Wiring fault
- Sensor element aged beyond calibration window
Symptoms
- Check-engine or charging-system warning light
- Charging may not start or may be interrupted
How to diagnose it
- Review freeze-frame data and observe live proximity circuit B data while inserting and removing the charging plug.
- Check whether plug recognition changes with movement of the connector or charging cable.
- With charging disconnected, inspect the inlet contacts and circuit B connector for dirt, wear, corrosion, or damage.
- Inspect accessible circuit B wiring for loose connections, chafing, or damage that could distort the signal.
- Test the circuit's signal response and sensor element against the manufacturer's specification to identify wiring faults or sensor drift.
Common fixes
- Clean the inlet contacts using the vehicle's approved method.
- Secure loose circuit B connectors and repair damaged terminals.
- Repair damaged or chafed proximity circuit B wiring.
- Replace a proximity sensor or inlet component confirmed to be outside specification.
Can I keep driving?
Driving is generally possible, but charging may not start or may be interrupted if the plug is not recognised consistently. Avoid forcing the plug or repeatedly bending the cable to obtain a connection.
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.