P0563 System voltage high
- System
- Powertrain - engine and transmission
What P0563 means
The official name, 'System voltage high', says which quantity was measured and what it was held against: the voltage of the vehicle's electrical system, as the module sees it on its own supply, compared with the upper limit that module is programmed to accept. Volts is the whole of the measurement — nothing about air, fuel, spark or exhaust enters this comparison. Its twin, 'System voltage low', is the same reading failing the limit at the bottom end instead.
This is a standard code. It means the same thing on every make of vehicle.
What the program shows for P0563
The Dashboard's System voltage gauge carries the program's own limits for that reading: green from 13.2 to 14.8 V, amber outside that, and red below 12.8 V or above 15.2 V, on a scale that runs to 18 V. Separately, while the adapter is waking up, the Adapter traffic screen logs the socket voltage the adapter measured at the connector itself.
The Dashboard shows Vehicle speed, Engine speed with its warm-idle band, Relative throttle, Throttle actuator and System voltage, plus Oil temp (the program has no oil pressure reading). The Trip screen keeps Distance, Average speed, Time moving and Time idling, and the Analysis screen's At idle table gives the idle rpm for a recording. Compare shows idle rpm and throttle Before and After between two recordings.
See how the program shows a code →