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2009 Chevrolet Malibu Hybrid – Service Charging System With P0621

Aug 15
1 min read

Updated: Aug 15

CUSTOMER CONCERN

Customer states the Service Charging System message is displayed. ECM DTC P0621 is stored.

CAUSE

L-terminal command and Orange-wire voltage testing confirmed the control circuit was operating but the alternator did not respond correctly, identifying an internal alternator failure.

CORRECTION

Remove and replace alternator. Clear DTC P0621 and verify charging-system output and L-terminal command response.

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2009 Chevrolet Malibu Hybrid – Service Charging System With P0621

CUSTOMER CONCERN

CAUSE

CORRECTION

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