Error code
OBD2 P0621
OBD2P0621
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Generator Lamp/L Terminal Circuit.
Severity
moderateCan continue driving but should address the issue soon.
Summary
P0621 indicates an issue with the alternator warning lamp circuit, which is part of the engine control module (ECM).
Common Causes
- Wiring issues related to the alternator warning lamp
- Faulty ECM
Fixes
FAQ
What does P0621 mean?
P0621 indicates a malfunction in the circuit that controls the alternator warning lamp, which is part of the ECM.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
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- P0606ECM/PCM Processor
- P0607Control Module Performance
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- P0610Control Module Vehicle Options Error
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