P0621
Generator Lamp L Control Circuit Malfunction
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0621 means
- The fault code P0621 indicates that there is an issue with the L terminal circuit, which is responsible for monitoring the generator or alternator and ensuring that it is functioning properly. This may cause the battery to not charge properly or the vehicle to stall.
Possible symptoms
- Battery not charging properly
- Illuminated battery or charging system warning light
- Engine stalling or not starting
- Electrical system malfunctions (e.g. power windows, radio, etc.)
Possible causes
- Faulty generator or alternator
- Damaged or corroded wiring in the L terminal circuit
- Failed battery
- Failed engine control module (ECM)
Related parts
- Generator Lamp: Bulb on the Instument Panel that denotes a fault in the generator system. This car's bulb doesn't work
Possible solutions
- Replace the generator or alternator
- Check and repair any damaged or corroded wiring in the L terminal circuit
- Replace the battery if necessary
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0621 on OBD DashX
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