Code result
P0621
Generator Lamp L Control Circuit Malfunction
Moderate severity
What it means
The control circuit for the generator warning lamp output (L terminal) reports a fault.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Lamp circuit open or shorted
highOne of the most commonly reported causes for this code — check this first.
Alternator regulator fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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