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P0621

Overview

Code

P0621

Code Type

P

Code Class

P0

System

Engine

Severity Level

High

Emissions Related

false

Drivability Impact

Major

Diagnostic Protocol

OBD2

Freeze Frame Useful

true

Code Definition

Diagnostic trouble code P0621 indicates an issue with the alternator field control circuit

Symptoms

Battery light on; Difficulty starting

Overview applies to this diagnostic code.

Affected Systems

On This Page

  • Code Definition

  • Symptoms

  • Affected Systems

  • Possible Causes

  • Diagnostic Steps

  • Drive Safety Notes​

More Resources

Alternator field control circuit

Possible Causes

Faulty alternator; Wiring issue

Diagnostic Steps

1 Inspect alternator field control circuit 2 Test alternator output

Drive Safety Notes

Alternator issues can result in loss of electrical power

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