What it means
The ECM detects a high fault on the battery charger hybrid/ev battery output current sensor circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The charger’s output-current sensor measures current flowing between the onboard charger and the high-voltage battery. The control module monitors its signal while charging and sets P0D54 when the signal is higher than the circuit should produce, so it cannot rely on that current reading.
Common causes
Most likely first.
- Signal circuit short to power
- Open or high-resistance wiring or connector
- Faulty current sensor
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
How to diagnose it
- Review freeze-frame data and charger live data to see whether the high reading occurred during charging or persisted when charging was inactive.
- With the vehicle safely powered down according to its service instructions, inspect the output-current sensor connector and accessible wiring for damage, moisture, corrosion, or a loose fit.
- Check the sensor signal wire for a short to power and inspect its terminals for poor contact or high resistance.
- Compare the sensor signal and reported battery charging current with the manufacturer's diagnostic specifications under the stated test conditions.
- If the wiring and connections pass, test the output-current sensor and charger control using the manufacturer's procedure before replacing parts.
Common fixes
- Reconnect or repair a loose, corroded, or damaged sensor connector.
- Repair signal wiring shorted to power or a high-resistance connection.
- Replace the battery charger output-current sensor if it fails the specified test.
- Repair or replace the charger control unit if its sensor input is faulty.
Can I keep driving?
Avoid relying on electric power or attempting long trips while the vehicle has reduced power or charging faults. Stop safely if power drops sharply, and arrange diagnosis because charging may fail and the vehicle may enter limp mode.
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.