P1148 INFINITI Possible Causes
For 2005 and later models:
- Faulty Air/Fuel Ratio Sensor 1, Bank 1
- Air/Fuel Ratio Sensor 1, Bank 1 Circuit Open or Shorted
- Electrical Connection of Air/Fuel Ratio Sensor 1, Bank 1 Circuit
For models before 2005:
- Faulty Heated Oxygen Sensor 1, Bank 1
- Heated Oxygen Sensor 1, Bank 1 Circuit Open or Shorted
- Electrical Connection of Heated Oxygen Sensor 1, Bank 1 Circuit
How to Fix P1148 INFINITI Code?
Start by checking the “Possible Causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
When is the Code Detected?
The closed-loop control function for Bank 1 does not operate even when the vehicle is running under specified conditions; the closed-loop control function for Bank 2 does not operate even when the vehicle is running under specified conditions.
Possible Symptoms
- Check Engine Light On (or Service Engine Soon Warning Light)
P1148 INFINITI Meaning
The Engine Control Module (ECM) performs an on/off control of the Air/Fuel (A/F) Ratio/Heated Oxygen Sensor 1 heater corresponding to the engine operating condition to maintain the Air/Fuel (A/F) Ratio/Heated Oxygen Sensor 1 heater element temperature within the specified range.