P0D27

What it means

P0D27 means the control unit monitoring the on-board battery charger measured the incoming charging voltage below the expected range while charging was requested. It is mostly seen on plug-in hybrids and electric vehicles. The low reading may come from the supply, the cable, the charge inlet or the charger itself.

Symptoms

• Charging will not start or stops part-way through
• Charging is much slower than normal
• Charging warning light or message on the dash
• Charge port indicator shows a fault or flashes unusually
• Fault only appears at certain charge points or locations

Possible causes

• Poor or low supply voltage at the socket, wallbox or public charge point, such as overloaded circuit or voltage drop on a long runlikely
• Faulty or damaged charging cable or portable charging unitlikely
• Damaged, corroded, wet or heat-marked charge inlet pins or connectorpossible
• Loose or corroded connections or wiring fault between the inlet and the on-board chargerpossible
• Low 12 V battery voltage upsetting charger control or voltage monitoringpossible
• Faulty on-board charger or its voltage sensing circuitrare
• Outdated charger control software where the manufacturer has documented a known faultrare

How to diagnose

1. Read all stored and pending codes and freeze frame data, noting when and how the fault set, and look for other charger or high-voltage codes.
2. Try a different charge point or socket, and a different known-good cable, to see whether the fault follows the supply or the car.
3. Have a qualified electrician check the supply voltage under load at the socket or wallbox, and check its protective devices and wiring.
4. Inspect the cable, plug and car charge inlet for damage, burning, water, debris, bent pins or corrosion.
5. Check the 12 V battery condition and charging voltage, as low system voltage can affect charger control.
6. Only if trained and certified for high-voltage systems, follow the manufacturer procedure to isolate the system and inspect wiring and connectors to the on-board charger.
7. Check live data for charger input voltage and compare it with the measured supply voltage, following the model-specific procedure.
8. Check for manufacturer service bulletins or software updates relating to the charger for this model and engine.

How to fix

• Correct the supply problem, such as a poor circuit, loose connection or voltage drop, using a qualified electrician.
• Replace a damaged charging cable or portable charging unit.
• Repair or replace a damaged charge inlet or its connector and terminals.
• Repair wiring faults or clean and secure connectors between the inlet and the on-board charger.
• Recharge or replace a weak 12 V battery and repair any 12 V charging fault.
• Replace the on-board charger if testing confirms an internal fault, or apply a manufacturer software update if a known calibration fault applies.

Can I keep driving?

Nearby codes

• P0D26GenericBattery Charger System Precharge Time Too Long
• P0D28GenericBattery Charger Input Voltage Too High