What it means
The battery charger monitors the voltage supplied at its input during charging. It sets this code when that voltage falls below the expected range.
How it works
The battery charger monitors the voltage supplied at its input while charging. P0D27 sets when that input voltage falls below the expected range, which can limit or interrupt charging.
Common causes
Most likely first.
- Low or unstable supply voltage
- Charging inlet, wiring, or connection fault
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
How to diagnose it
- Read freeze-frame and live input-voltage data to determine whether the low reading occurred at plug-in, during charging, or when charging stopped.
- Check the charging supply and charging inlet for an obvious interruption, damaged connector, contamination, or loose fit.
- If safe and accessible, try a known suitable charging supply to see whether the low-voltage condition follows the original supply.
- Inspect accessible input wiring and connections for damage or poor contact, following the vehicle's safety instructions.
- Measure the input circuit under the conditions specified by the manufacturer and compare the result with its specification.
Common fixes
- Reconnect the charging plug fully or clean a connector as permitted by the manufacturer.
- Repair damaged inlet wiring or terminals.
- Correct a low or unstable charging supply identified during diagnosis.
- Replace the charger if its input-voltage monitoring or operation fails the manufacturer's tests.
Can I keep driving?
Charging may be slow or stop, so confirm the vehicle has enough range before driving. If the inlet or plug is hot, damaged, or discoloured, stop charging and have it checked before using it again.
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.