Insufficient Coolant Temperature for Closed Loop Fuel Control
2000-2002 Rolls-Royce Corniche 6.75L V8
Description
The engine is not reaching normal operating temperature quickly enough for the PCM to enter closed-loop fuel control.
Symptoms
- Check Engine Light
- Poor fuel economy
- Extended warmup time
- Rich exhaust smell
Common Causes
- Stuck-open thermostat
- Faulty ECT sensor
- Cooling fan running constantly
- Low coolant level
Diagnostic Steps
- Monitor ECT warmup time (should reach 160°F within 5-10 min)
- Test thermostat
- Check cooling fan operation
- Test ECT sensor
Repair Notes
Replace thermostat. Most common cause.
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
P0125 on Other Vehicles
Rolls-Royce Cullinan
2019-2024 6.75L V12 Twin Turbo
Rolls-Royce Dawn
2016-2024 6.6L V12 Twin Turbo
Rolls-Royce Ghost
2010-2024 6.6L V12 Twin Turbo
Rolls-Royce Phantom VII
2003-2017 6.75L V12
Rolls-Royce Phantom VIII
2018-2024 6.75L V12 Twin Turbo
Rolls-Royce Silver Seraph
1998-2002 5.4L V12
Rolls-Royce Silver Spirit
1990-1998 6.75L V8
Rolls-Royce Silver Spur
1990-1998 6.75L V8
Common Questions
What does code P0125 mean on a 2000-2002 Rolls-Royce Corniche?
P0125 stands for "Insufficient Coolant Temperature for Closed Loop Fuel Control". The engine is not reaching normal operating temperature quickly enough for the PCM to enter closed-loop fuel control.
What are the symptoms of P0125 on a Rolls-Royce Corniche?
Common symptoms of P0125 include: Check Engine Light, Poor fuel economy, Extended warmup time, Rich exhaust smell.
What causes P0125 on a 2000-2002 Rolls-Royce Corniche?
Common causes of P0125 include: Stuck-open thermostat, Faulty ECT sensor, Cooling fan running constantly, Low coolant level.