What it means
The proximity detection circuit A (SAE J1772 PD signal) reports a circuit a condition. Charging cable plug detection impaired.
At a glance
- Usually lights the check-engine light
How it works
Proximity detection circuit A carries the SAE J1772 plug-detection signal from the charge inlet to the vehicle’s charging controls. The module monitors this circuit to determine whether a charging connector is present and sets P0D56 when circuit A has a fault that prevents reliable plug detection.
Common causes
Most likely first.
- Charge inlet contacts dirty
- Wiring fault
Symptoms
- Charging system warning light may come on
- Vehicle may not recognize that a charging plug is connected
- Charging may not start
How to diagnose it
- Check charging-system messages and live plug-status data while connecting and removing the charging connector to confirm whether the vehicle detects it.
- Inspect the charge inlet and connector contacts for dirt, moisture, corrosion, bent pins, or physical damage.
- Check the circuit A wiring and inlet connector for looseness, chafing, or damage between the inlet and the charging controls.
- With the vehicle powered down as specified by the manufacturer, test circuit A continuity and check for unintended shorts using the manufacturer's procedure.
- If the inlet and wiring pass, test the proximity-detection input at the charging control module to identify a possible module-side fault.
Common fixes
- Clean and dry the charge inlet contacts using the manufacturer's approved method.
- Repair damaged or loose proximity-detection wiring or connector terminals.
- Replace a damaged charge inlet if its circuit A contacts fail inspection or testing.
- Repair the charging-control input if the inlet circuit tests correctly.
Can I keep driving?
The fault mainly affects plug recognition, so charging may not begin even if the vehicle drives normally. Do not force a connector into the inlet; use another suitable charging option if available and address the fault before depending on a charge.
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.