P1646moderate severityPowertrain
Front Heated O2 Sensor Bank 1 Fault
on 2002 Volvo S80 2.9L I6 · AWD
What this code means
The ECM detected a fault in the front (upstream) heated oxygen sensor on Bank 1. The sensor signal or heater circuit is not operating within specification.
Symptoms
- Check Engine Light
- Poor fuel economy
- Rough idle
- Failed emissions test
Common causes
- Faulty O2 sensor Bank 1
- O2 sensor heater failure
- Exhaust leak near sensor
- Wiring damage to sensor
- Connector corrosion
Diagnostic steps
- Test O2 sensor signal voltage and switching rate
- Test heater circuit resistance
- Check for exhaust leaks near sensor
- Inspect wiring and connector
- Compare Bank 1 vs Bank 2 sensor performance
Repair notes
Replace the front heated O2 sensor on Bank 1.
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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