Engine-CodesPontiac – P0157 Pontiac

P0157 Pontiac Code - HO2S Circuit Low Voltage Bank 2 Sensor 2

Quick Answer

The P0157 diagnostic trouble code (DTC) for Pontiac vehicles refers to a problem in the HO2S (Heated Oxygen Sensor) Circuit on Bank 2 Sensor 2, indicating that there is low voltage detected in the sensor. Common causes include Faulty oxygen sensor, Damaged wiring or connectors leading to the sensor, Exhaust leaks near the sensor. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means
P0157 Pontiac indicates HO2S Circuit Low Voltage Bank 2 Sensor 2.
Common causes
Common causes include Faulty oxygen sensor, Damaged wiring or connectors leading to the sensor, Exhaust leaks near the sensor.
Severity
Moderate - service should be scheduled soon.
Can I drive?
The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Table of contents Created and updated by William Orellana on Sep 12, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0157 Pontiac Description

The P0157 diagnostic trouble code (DTC) for Pontiac vehicles refers to a problem in the HO2S (Heated Oxygen Sensor) Circuit on Bank 2 Sensor 2, indicating that there is low voltage detected in the sensor. The HO2S is responsible for monitoring the oxygen levels in the exhaust gases and providing feedback to the engine control module (ECM) to adjust the air-fuel mixture for optimal combustion. In this case, Bank 2 refers to the side of the engine where cylinder #2 is located, and Sensor 2 indicates that it is the downstream sensor located after the catalytic converter.

OBDII Code P0157 Pontiac - HO2S Circuit Low Voltage Bank 2 Sensor 2
P0157 Pontiac Code - HO2S Circuit Low Voltage Bank 2 Sensor 2

Common Causes of P0157 Pontiac

  1. Faulty oxygen sensor.
  2. Damaged wiring or connectors leading to the sensor.
  3. Exhaust leaks near the sensor.
  4. Issues with the ECM or related components.
  5. Contaminated or deteriorated sensor due to age or environmental factors.

Symptoms of P0157 Pontiac

  1. Check Engine Light is illuminated on the dashboard.
  2. Decreased fuel efficiency and increased fuel consumption.
  3. Rough idling or stalling of the engine.
  4. Poor acceleration and overall engine performance.
  5. Increased emissions output.

How to Fix P0157 Pontiac

  1. Begin by using an OBD-II scanner to confirm the P0157 code and verify that it is related to Bank 2 Sensor 2.
  2. Inspect the wiring and connectors leading to the oxygen sensor for any signs of damage or corrosion. Repair or replace as needed.
  3. Test the oxygen sensor using a multimeter to check for proper voltage output. Replace the sensor if it is faulty.
  4. Clear the DTC from the ECM memory using the OBD-II scanner and monitor the vehicle for any recurring issues.
  5. Perform a test drive to ensure that the repair has resolved the problem and that the Check Engine Light does not reappear.

Cost to Fix P0157 Pontiac

The cost of repairing a P0157 code on a Pontiac vehicle can vary depending on the specific cause of the issue and the parts needed for replacement. On average, the cost of replacing an oxygen sensor can range from $100 to $300, including parts and labor. Additional costs may apply if wiring repairs or ECM diagnostics are required. It is advisable to consult with a qualified mechanic or auto repair shop for a more accurate estimate based on the vehicle's make and model, as well as local labor rates. Keep in mind that diagnosis time and labor rates can vary, so it's recommended to inquire about these details before proceeding with the repair.

Tech Notes for P0157 Pontiac

Replacing the Rear Heated Oxygen Sensor (HO2S) Bank 2 usually takes care of the problem.

Need more information about the P0157 Pontiac code?

Need more information on how to fix the P0157 Pontiac code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0157 Pontiac code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0157 Pontiac Code

No Frequently Asked Questions about P0157 Pontiac Code found.

Discuss the causes and fixes for P0157 Pontiac OBDII Code