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 PCM monitors alternator output deviation from the signal of the FR terminal of the alternator when the engine is running
PCM sets DTC P0625 if the PCM detects output duty signal lower than the possible range of a properly operating alternator.
Item
Detecting Condition
Possible Cause
DTC Strategy
Electrical Check
Short to battery in harness
Poor connection or damaged harness
Enable
Conditions
Case1
Time after ignition ON > 0.1sec.
Engine speed=0
No main relay error
Case2
Engine speed >0rpm
No relevant failure
Battery voltage <16V
600< Engine speed(rpm) <4000
Coolant temp. >73?(140?)
Threshold
Value
Alternator load <15%
Alternator load <2%
Diagnostic
Time
1sec.
20sec.
MIL On Condition
-
Fig.1) Idle Status
Fig.2) Electrical Load (Head Lamp and Defrost are ON
Duty(+) from FR terminal is increased if electrical loads are ON (Head Lamp and Defrost are ON)
PCM controls generation of alternator with duty from FR terminal when electrical Loads turn on