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 | |
Case 1 | DTC Strategy |
•
IG ON |
•
Circuit shorts to ground
•
Charging system |
Enable Conditions |
•
More than 3 sec after IG ON
•
Engine stop
•
No fault on a main rely
•
10 V＜ Battery voltage ＜ 16 V | ||
Threshold Value |
•
FR circuit Duty < 80%
•
Minimum voltage of Low level duty signal ≥ 1.5V | ||
Diagnostic Time |
•
1 sec. | ||
Case 2 | DTC Strategy |
•
Engine running | |
Enable Conditions |
•
More than 100 sec after engine running
•
Engine RMP : 600rpm ~ 4000rpm
•
No fault on a main rely
•
10 V ＜ Battery voltage ＜ 16 V | ||
Threshold Value |
•
FR circuit Duty < 3% | ||
Diagnostic Time |
•
20 sec. | ||
Mil On Condition |
•
No MIL | ||
The normal FR circuit duty signal under IG ON state
→ Low level voltage ＜ 1.5V : Normality , Low level voltage ≥ 1.5V : Abnormality
The normal FR circuit duty signal under engine running state
→ 5% < FR circuit duty < 95% : Normality , FR circuit duty < 3% : Abnormality
