P1148 Infiniti Code - Closed Loop Control Function Bank 1
Quick Answer
The Engine Control Module (ECM) performs ON/OFF duty control of the Air Fuel Ratio (A/F)/Heated Oxygen Sensor 1 heater corresponding to the engine operating condition to keep the temperature of Air Fuel Ratio (A/F)/Heated Oxygen Sensor 1 element at the specified range. Common causes include For Models 2005 and up:, Faulty Air Fuel Ratio Sensor 1 Bank 1, Air Fuel Ratio Sensor 1 Bank 1 circuit is open or shorted. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1148 Infiniti indicates Closed Loop Control Function Bank 1.
- Common causes
- Common causes include For Models 2005 and up:, Faulty Air Fuel Ratio Sensor 1 Bank 1, Air Fuel Ratio Sensor 1 Bank 1 circuit is open or shorted.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1148 Infiniti Description
What are the Possible Causes of the DTC P1148 Infiniti?
-
For Models 2005 and up:
- Faulty Air Fuel Ratio Sensor 1 Bank 1
- Air Fuel Ratio Sensor 1 Bank 1 circuit is open or shorted
- Air Fuel Ratio Sensor 1 Bank 1 circuit electrical connection For Models before 2005:
- Faulty Heated Oxygen Sensor 1 Bank 1
- Heated Oxygen Sensor 1 Bank 1 circuit is open or shorted
- Heated Oxygen Sensor 1 Bank 1 circuit electrical connection
How to Fix the DTC P1148 Infiniti?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
2004-2005 Infiniti FX35 2WD
2004-2005 Infiniti FX35 4WD
2004-2005 Infiniti G35 Sedan 2WD
2004-2005 Infiniti G35 Sedan 4WD
Infiniti Factory Service Bulletin OBDII Code P1148
The bulletin suggests reprogramming the Engine Control Module (ECM) first before replacing any parts.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1148 Infiniti code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P1148 Infiniti code?
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Need Help with the Code?
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Information for Specific Infiniti Models
- P1148 2003 Infiniti G35 — Closed Loop Control Function Bank 1
- P1148 2004 Infiniti G35 — Closed Loop Control Function Bank 1
- P1148 2005 Infiniti G35 — Closed Loop Control Function Bank 1
- P1148 2006 Infiniti G35 — Closed Loop Control Function Bank 1
Frequently Asked Questions about P1148 Infiniti Code
What does the OBD-II code P1148 mean for an Infiniti?
The P1148 code indicates a problem with the closed-loop control function for Bank 1, often caused by issues with the air-fuel ratio sensor or its circuit.
What are the common symptoms of the P1148 code in an Infiniti?
Symptoms may include the check engine light turning on, decreased fuel efficiency, rough idling, or poor engine performance.
What causes the P1148 code in an Infiniti vehicle?
Common causes include a faulty air-fuel ratio (A/F) sensor, damaged wiring or connectors, a malfunctioning engine control module (ECM), or exhaust system leaks.
How can I diagnose the P1148 code in my Infiniti?
Start by checking the air-fuel ratio sensor and its wiring for damage, inspecting for exhaust leaks, and using a scan tool to monitor sensor data.
Can I drive my Infiniti with the P1148 code active?
Driving with this code is not recommended as it may lead to reduced fuel efficiency, increased emissions, and potential damage to the catalytic converter.
How is the P1148 code repaired in an Infiniti?
Repairs may include replacing the air-fuel ratio sensor, repairing wiring or connector issues, fixing exhaust leaks, or reprogramming the ECM if necessary.
How much does it cost to fix the P1148 code on an Infiniti?
Costs can vary but typically range from $200 to $500 for parts and labor, depending on whether the air-fuel ratio sensor or other components need replacement.
Can a dirty air filter cause the P1148 code on an Infiniti?
While unlikely, a severely clogged air filter can affect engine performance and air-fuel ratio, potentially contributing to this code.
What tools are needed to fix the P1148 code on an Infiniti?
Essential tools include an OBD-II scanner, a multimeter for electrical testing, and basic hand tools to inspect and replace components.
Does the P1148 code always mean the air-fuel ratio sensor is bad?
No, the code can also be triggered by wiring issues, exhaust leaks, or ECM problems, so thorough diagnosis is essential before replacing parts.
Discuss the causes and fixes for P1148 Infiniti OBDII Code
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