The purpose of the System Voltage is to detect an excessively low or high system voltage that may be caused by a malfunctioning charging system.
System Voltage is the ignition voltage potential at the Powertrain Control Module (ECM)
ECM measures and compares voltage from ignition key and each relay. With this mechanism, ECM knows if the main relay switch turns on after IG on or if turns OFF after IG off.
If ECM detects malfunction in power supply system, ECM sets DTC P0560.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage check
Poor connection
Open / Short
Main relay
Enable Conditions
Engine speed = 0rpm
Main relay condition off
Threshold Value
Counter of nonplausible voltage detection (higher than 0V) = 5 times
Diagnostic Time
Continuous
MIL ON Condition
DTC only