P1276moderate severityPowertrain
Air Fuel Ratio (A/F) Sensor 1 Circuit (Bank 2)
on 2003 Infiniti FX45 4.5L V8 · AWD
What this code means
The ECM detected a fault in the air/fuel ratio sensor 1 circuit on bank 2. Roughly equivalent to generic O2 sensor circuit codes like P0150.
Symptoms
- Check engine light on
- Poor fuel economy
- Rough running
Common causes
- Faulty A/F sensor
- Sensor wiring or connector fault
- Exhaust leak near sensor
- ECM fault
Diagnostic steps
- Retrieve freeze frame data
- Check A/F sensor wiring and connector
- Measure sensor signal with scan tool
- Replace A/F sensor if faulty
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1