P0626moderate severityPowertrain
Generator Field/F Terminal Circuit Low
on 2020 Ford F-150 5.0L V8 Coyote · RWD
What this code means
The PCM detected low voltage on the generator (alternator) field control circuit. This can cause charging problems and battery drain.
Symptoms
- Battery warning light on
- Dim headlights
- Battery not charging
Common causes
- Faulty alternator/generator
- Corroded field terminal connection
- Damaged wiring to field circuit
- Faulty PCM
Diagnostic steps
- Scan for related charging codes
- Inspect generator field wiring and connectors
- Measure voltage at field terminal
- Test alternator output under load
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P0001
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P0001
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P0002
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P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0005
Fuel Shutoff Valve A Control Circuit/Open