Onboard Charger Ground Fault Detected
2012-2017 Buick Regal 2.4L I4 Hybrid
Description
The onboard charger has detected a ground fault condition during charging, which triggers an immediate charge session stop for safety.
Symptoms
- Charging stops immediately
- Ground fault indicator on EVSE
- Charge session will not restart
- Intermittent charge interruptions
- Works at some locations but not others
Common Causes
- Ground fault in vehicle wiring
- EVSE ground fault sensitivity
- Moisture in charge port
- Vehicle HV insulation degradation
- Home wiring ground issue
Diagnostic Steps
- Test at multiple EVSE locations
- Inspect charge port for moisture
- Check vehicle HV isolation resistance
- Test home electrical outlet grounding
- Read OBC ground fault trip data
Repair Notes
Dry charge port if moisture is present. Test HV system isolation. Have electrician verify home outlet grounding. Replace OBC if vehicle-side ground fault confirmed.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P3404 on Other Vehicles
Common Questions
What does code P3404 mean on a 2012-2017 Buick Regal?
P3404 stands for "Onboard Charger Ground Fault Detected". The onboard charger has detected a ground fault condition during charging, which triggers an immediate charge session stop for safety.
What are the symptoms of P3404 on a Buick Regal?
Common symptoms of P3404 include: Charging stops immediately, Ground fault indicator on EVSE, Charge session will not restart, Intermittent charge interruptions, Works at some locations but not others.
What causes P3404 on a 2012-2017 Buick Regal?
Common causes of P3404 include: Ground fault in vehicle wiring, EVSE ground fault sensitivity, Moisture in charge port, Vehicle HV insulation degradation, Home wiring ground issue.