DTC P0620-49: Generator Control Circuit Internal Electronic Failure [11/2023 - ]: Description

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The alternator performs self-diagnosis of its internal circuits to detect malfunctions (open or short circuits).

The ECM receives the result via LIN communication and stores a DTC.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate	Note
P0620-49	Generator Control Circuit Internal Electronic Failure	All of the following conditions are met (1 trip detection logic): Ignition switch ON. Except during engine cranking. Auxiliary battery voltage is 10.5 V or higher. No malfunction in the LIN communication system. Open or short in EXC circuit, or abnormal waveform for PH circuit.	Generator assembly	Does not come on	Charge warning is displayed	SAE Code: P0620