What it means
The charge port door B unlock control reports a circuit low condition. Door cannot be commanded to unlock reliably.
At a glance
- Usually lights the check-engine light
How it works
The charge port door B unlock actuator is driven through an electrical control circuit. The module monitors the circuit while commanding the actuator. This code sets when the monitored signal is lower than expected, which can result from a short to ground, an open or resistive connection, or an internal actuator fault.
Common causes
Most likely first.
- Signal circuit shorted to ground
- Internal actuator or circuit fault
- Open or high-resistance wiring
Symptoms
- Charge-port door B may not unlock reliably
How to diagnose it
- Record freeze-frame data and check for other charge port door B or actuator circuit codes before clearing anything.
- Command door B to unlock with a scan tool and observe whether the actuator responds.
- Inspect the door B actuator connector and wiring for chafing, corrosion, water entry, or a wire touching ground.
- Check circuit continuity and resistance for an open or high-resistance connection, following the manufacturer's wiring information.
- Test for a short to ground and compare the circuit signal during an unlock command with the manufacturer's specification.
- Test the actuator separately as directed by the manufacturer's procedure, then replace it only if the wiring checks out.
Common fixes
- Clean and secure a corroded or loose door B actuator connector.
- Repair an open, high-resistance, or grounded section of the unlock circuit.
- Replace the charge port door B unlock actuator if it has an internal fault.
Can I keep driving?
You may be unable to open charge port door B reliably, which can prevent access to that charging inlet. Do not force the door or connector; the fault does not by itself indicate an engine or emissions problem.
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.