The ECM provides ground to one side of the coil of the main relay and the other side is connected to the battery. The ECM monitors battery voltage and the voltage after the main relay.
During engine running, if system voltage is below 11V or the battery power input line has a problem, ECM sets P0562.
Item | Detecting Condition | Possible cause | |
DTC Strategy |
•
Voltage too low |
•
Poor connection
•
Open or short in circuit
•
Faulty charging system
•
Faulty main relay
•
Faulty ECM | |
Enable Conditions | Case1 |
•
Engine works | |
Case2 |
•
- | ||
Threshold value | Case1 |
•
System voltage < 11V | |
Case2 |
•
Open or short to ground in memory power line | ||
Diagnosis Time | Case1 |
•
Continuous | |
Case2 |
•
Continuous (More than 5 sec.failure for every 10 sec.test) | ||
MIL On Condition |
•
3 driving cycle |
Coil Resistance | 70Ω ~ 120Ω |
Fig.1) Normal waveforms of COM, FR terminal of alternator at idle.
Fig.2) Normal waveforms of COM, FR terminal of alternator under high electronic load condition