P0125moderate severityPowertrain
Insufficient Coolant Temperature for Closed Loop Fuel Control
on 2000 Volvo S80 2.9L I6 · AWD
What this code means
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.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
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
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1