What it means
The proximity detection circuit B (SAE J1772 PD signal) reports a circuit 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 proximity-detection signal, which helps the charging system recognise the plug and its connection at the inlet. The control module monitors this circuit for a fault that could prevent reliable plug detection; this code does not by itself specify whether the signal is low, high, or out of range.
Common causes
Most likely first.
- Charge inlet contacts dirty
- Wiring fault
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 charging-system status to see when proximity detection circuit B faulted.
- Check whether the charge inlet recognises the plug consistently when it is inserted and removed.
- With charging disconnected, inspect the inlet contacts and the vehicle-side proximity circuit B terminals for dirt, damage, or corrosion.
- Inspect accessible wiring for loose connections, chafing, or damage between the inlet and the control module.
- Test circuit B continuity and signal behaviour using the manufacturer's wiring information and specification.
Common fixes
- Clean debris from the charge inlet using the vehicle's approved method.
- Reconnect or secure a loose proximity circuit B connection.
- Repair damaged wiring or corroded terminals in circuit B.
- Replace a confirmed faulty inlet or proximity-detection component.
Can I keep driving?
The vehicle can usually be driven, but charging may fail to start or may be interrupted because the plug is not detected reliably. Do not force the connector into the inlet; arrange another charging option if connection remains unreliable.
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.