Alternator output and power demand of all electrical loads and systems must be matched to each other as ideally as possible so that the entire system is reliable and trouble-free in operation. The ECM monitors alternator output deviation from the signal of the FR terminal of the alternator when the engine is running.
ECM sets DTC P0626 if the ECM detects that the alternator's output duty signal is 0%.
Item
Detecting Condition
Possible Cause
DTC Strategy
Input signal check
Open or Short to Power in harness
Faulty charging system
Enable Conditions
Battery voltage < 16V
Engine speed : 600 ~ 4000
Engine coolant temp. > 75?
Threshold Value
Duty calculated by Alternator PWM signal = 0%
Diagnostic Time
100sec.
MIL ON Condition
DTC only