What does this code mean?
One of the car computers reported an excessively high supply voltage. P0563 calls for checking the electrical supply and verifying the reading. The alternator, which generates electricity while the engine runs, is a possible area to investigate, not a confirmed failure.
Locate the reported problem
External charging or a regulation issue may be relevant. Tell the workshop about chargers or starting equipment used before the code appeared.
Read it with the other codes
P0562 reports low voltage. For P0563, repeated parts replacement without checking actual charging behavior can leave the source of the high reading unresolved.
Possible causes to investigate
These are possibilities, not a diagnosis or a ranked list of failed parts.
- A battery, charging-system or external-charger condition affecting system voltage.
- A supply connection, ground or measurement issue at the reporting module.
What to do first
- Record recent jump-starts, charging, battery replacement and whether the engine struggled to crank. Save codes from the complete report.
- Do not disconnect the battery with the engine running or touch hybrid/EV high-voltage components. A hot, swollen or leaking battery needs professional assistance.
What the workshop can check
Compare voltage at the battery and affected module during the relevant operating state. Check connections, voltage drops and charging control before choosing a battery, alternator or module; smart charging does not use one universal running-voltage target.
A useful question to ask
Was high voltage measured independently, and did it occur during normal running or external charging?
Your vehicle changes the next step
Year, make, model, engine and the complete code list matter. Cylinder layout, test conditions and repair procedures can differ. Use service information for the exact vehicle; a generic code does not establish an exact failed part.
Can I keep driving?
This page cannot decide whether your car is safe to drive. A flashing engine light, severe shaking, overheating, strong fuel smell or major power loss calls for prompt attention. Stop safely when needed, follow your handbook and seek assistance rather than continuing a test drive.
Terms in this guide
These words appear in the explanation. Select an underlined term in the text to reach its definition.
- Voltage
- The electrical difference that drives current, measured in volts. In a sensor code, high or low may describe this signal rather than the real temperature or pressure.
- Circuit, supply and ground
- A circuit includes the wiring and connections carrying electricity. Supply powers a component; ground is its electrical return. A fault in any of these can change a reading.
- Alternator
- Generates electricity while the engine runs to power the car and charge its battery.
- Control unit
- A car computer that receives measurements and controls the engine or another system. It may also be called a module, ECU, ECM or PCM.
- Range, threshold and performance
- A range is the expected interval; a threshold is a comparison limit. Performance describes whether something responds as expected, not necessarily how much power the engine makes.
- Crankshaft
- A shaft converting piston movement into rotation. Crankshaft and camshaft sensors help the engine control system know their positions.
Sources and scope
Definitions and general OBD context are cross-checked against the references below. Manufacturer documents describe specific vehicles and systems; their procedures and thresholds are not instructions for every make. This is educational guidance, not a vehicle-specific repair procedure.