Fix P0160: Mechanic’s solutions that WORKED

The code P0160: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2) indicates a malfunction in the oxygen sensor circuit, specifically pointing to no activity being detected in the second sensor on bank 2. This issue is typically caused by a faulty sensor, wiring problems, or exhaust leaks.

P0160 quick overview

Meaning	P0160: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
Is it serious?	It can lead to increased emissions, reduced fuel economy, and potential damage to the catalytic converter if not addressed.
Possible causes	– Faulty or incorrect O2 sensor – Wiring or connector issues – Exhaust leaks – Faulty PCM or need for PCM reprogramming
How to diagnose?	Inspect the O2 sensor for any visible damage or incorrect type. Check wiring and connectors for corrosion, breaks, or shorts. Test O2 sensor functionality using a multimeter or scan tool. Search for technical service bulletins (TSBs) related to the code for your specific vehicle model. Check for exhaust leaks near the sensor and along the exhaust system. Consult with a professional if PCM reprogramming or replacement is suspected.

In plain language, code P0160 means that one of the sensors that checks the exhaust gases isn’t working. This sensor, located after the catalytic converter, helps control emissions and fuel efficiency. When it’s not active, it can’t do its job, which might lead to more pollution and your car using more fuel.

How to fix P0160 – learn from mechanics

I looked into P0160 service cases at iatn.com website where in the private forums the mechanics seek advice from other mechanics. I looked up a bunch of cases to help you decide how to fix your knock sensor issue. They also always report the fix that worked for the vehicle so this section will be like having a real mechanic helping you solve your issue.

Case #1: Nissan

Vehicle Information 1999 Nissan Pathfinder LE, 3.3L engine

Issue + Repair History

• MIL (Malfunction Indicator Lamp) on
• Code P0160: Bank 2 Sensor 2 voltage high
• Previous repair: Installed a hard ground wire kit to ground the intake to the engine block

What Are People Suggesting to Fix Issue

• Check for a shorted sensor or faulty ground
• ECM (Engine Control Module) might be under federal warranty for 8 years and 80,000 miles
• Replace the rear O2 sensor along with the ECM

What Was the Final Fix

• Replaced the ECM under federal warranty and replaced the rear O2 sensor as per TSB NTB1-48A. The vehicle runs great after the repair.

Case #2: Chevrolet

Vehicle Information 2001 Chevrolet Express 1500, 5.0L engine

Issue + Repair History

• MIL (Malfunction Indicator Lamp) on
• Failing I/M with code P0160: No activity on bank 2 sensor 2
• No physical Bank 2 Sensor 2 present on the vehicle
• Scanner shows normal numbers for the other 3 sensors and 0.445 for B2S2 (open circuit)

What Are People Suggesting to Fix Issue

• Check if the scanner software is glitching
• Unplug the aft cat O2 sensor to see if it triggers any code
• Verify if the vehicle is indeed a 5.0L as the 5.7L has a B2S2 O2 sensor
• Consider a software issue with the scanner or PCM (Powertrain Control Module)
• Suggestion to reflash the PCM

What Was the Final Fix

• The vehicle was sent back to the dealer for a reflash of the computer in hopes of resolving the issue.

Case #3: Cadillac

Vehicle Information 2003 Cadillac CTS, 3.2L engine

Issue + Repair History

• MIL on with codes PO160 and P0161 indicating issues with bank 2 sensor 2
• Sensor reading abnormal voltages (5000 millivolts)
• Oil leak from valve cover onto the harness and connector for B2S2
• Replaced O2 sensor and valve cover gaskets, but issue persisted
• Misfire data showed misfires on cylinders 1, 3, and 5 (opposite bank)
• Wiring and harness routing checked and found correct

What Are People Suggesting to Fix Issue

• Possibility of PCM failure as it is common in these models
• Check for harness chafing on O2 sensor 2 Bank 2 before condemning PCM

What Was the Final Fix

• Replacing the PCM resolved the issue. A used PCM was initially tried but had communication issues. The original PCM was reprogrammed by a local Cadillac dealer, which fixed the problem.

Case #4: Isuzu

Vehicle Information 1999 Isuzu Rodeo LS, 3.2L engine

Issue + Repair History

• MIL on with code P0160 indicating no activity from bank 2 sensor 2
• O2 sensor shows no activity whether plugged in or unplugged, always reading 450mv
• Replaced rear O2 sensor on bank 2 but issue persisted

What Are People Suggesting to Fix Issue

• Check O2 sensor with meter or scope for a bad sensor, ground, or wiring
• Consider possibility of an open circuit and check the circuit between the computer and the O2 sensor
• Check all grounds and try to drive the O2 sensor to its limits to test PCM/wiring
• Check wiring integrity for the circuit, as the issue could be a bad PCM or a bad wire

What Was the Final Fix

• Upon checking wiring integrity, it was found that the rear O2 sensor on the other bank was shorted to ground, potentially affecting the other sensor. The customer chose not to repair or replace the harness at that time and decided to bring the vehicle back when due for smog. Further updates will be provided if the vehicle is repaired.

Case #5: Hyundai

Vehicle Information 2003 Hyundai Santa Fe GLS, 2.7L engine

Issue + Repair History

• MIL on with code P0160 indicating no O2 activity bank 2, sensor 2
• Replaced O2 sensor twice
• Ohmed all wires from PCM to O2 connector; all fine
• 12 volts on pin 3 from PCM as expected, but code persists
• Sensor stays fixed at about 424 mv

Other OBD2 Codes + Test Results

• No additional codes or test results mentioned

What Are People Suggesting to Fix Issue

• Check for the correct type of O2 sensor (titanium vs zirconium) as per Hyundai TSB# 03-36-012-1
• Ensure no exhaust leaks where the pipe attaches to the cats or the flex section
• Verify there’s no reprogramming needed for the PCM
• Test O2 sensor signal wire with hands and battery to check voltage response
• Consider using OE sensors as some aftermarket sensors may not work well
• Check with a dealer for possible reprogramming flash due to data change during production

What Was the Final Fix

• The issue was resolved by replacing the Bosch sensor with an Original Equipment (OE) sensor. The Bosch sensor was not compatible with the vehicle. After ensuring the fix was stable, the MIL did not return.

Advice	Description of Diagnostic Step
Check for correct O2 sensor type	Verify if the O2 sensor matches the vehicle’s requirements (titanium vs zirconium) as per technical service bulletins.
Inspect wiring and connectors	Examine the integrity of wiring and connectors between the O2 sensor and the PCM.
Consider using OE sensors	Prefer Original Equipment sensors over aftermarket ones, as compatibility issues can arise.
Check for exhaust leaks	Inspect the exhaust system for any leaks, especially around the catalytic converter and O2 sensors.
Verify PCM software	Check if there’s a need for PCM reprogramming or software updates.
Test O2 sensor functionality	Physically test the O2 sensor’s response to voltage changes to confirm its operation.
Consult technical service bulletins	Look for any manufacturer bulletins that might provide guidance specific to the vehicle model.