General Information

Engine Control

P0620 Alternator Control Circuit - General Information

Component Location





General Description

The alternator is duty controlled as current control by ECM with the battery voltage, current, temperature information from battery sensor. The more electrical load, the higher duty output.

DTC Description

If it is open or short in COM circuit of alternator. ECM sets DTC.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data
















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
Fig.3) Normal waveforms of COM, FR terminal of alternator at ig on under connector disconnected condition.
Fig.4) Normal waveforms of COM, FR terminal of alternator at idle under connector disconnected condition.