Generator Field Terminal Circuit Low
Voltage on the alternator F terminal (field excitation) is below threshold — open or short to ground in the excitation path.
Affected components
- Alternator
- Alternator wiring
Common causes
- High likelihood: Field circuit open or shorted to ground
- Medium likelihood: Alternator brushes worn
- Low likelihood: Connector pins corroded - high contact resistance
Possible symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.