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 set DTC P0620 If it is open or short in Control circuit of alternator. If this DTC is set, Idle stop is not performing.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Signal check | 1. Open or Short in harness 2. Poor connection or damaged harness |
Enable Conditions |
•
Desired alternator voltage duty cycle ≥ 3.12%, ≤ 94.5%
•
Engine speed >240rpm
•
Battery voltage <16V, >10.73V | |
Threshold Value |
•
Open or Short circuit | |
Diagnostic Time |
•
Continuous | |
MIL On Condition |
•
DTC only(Idle stop forbidden) |
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
