P0161
Low SeverityO2 Sensor Heater Circuit (Bank 2, Sensor 2)
Emissions System
What Does P0161 Mean?
Heater failure in downstream O2 sensor bank 2.
Common Fix
Replace O2 sensor
Estimated Cost (DIY)
$25 - $80
Common Causes
How to Diagnose P0161
- 1Check fuse
- 2Measure heater resistance
- 3Replace sensor
OEM Diagnostic Flowchart
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Read live data and freeze frame for P0161 to pinpoint the cause before buying parts.
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Related Resources
Repair guides, symptom pages, and wiring diagrams related to P0161.
OEM Manual Evidence
Browse →A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali AWD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...
A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali 2WD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...
A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-6.0L Service Manual | Operation CHARM Operation CHARM : Car repair...
A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-5.3L Service Manual | Operation CHARM Operation CHARM : Car repair...
Related Symptoms
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Exact Repair Workflows
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Open the exact repair flow most commonly associated with P0161 on this vehicle.
Open the exact repair flow most commonly associated with P0161 on this vehicle.
Open the exact repair flow most commonly associated with P0161 on this vehicle.
Related Codes
The heater in the downstream O2 sensor on bank 1 has failed.
Heater failure in the upstream O2 sensor on bank 2.
The heater circuit for the downstream (post-cat) O2 sensor on bank 1 has failed. This sensor monitors catalytic converter efficiency.
Frequently Asked Questions
- Is this the cheapest O2 sensor to replace?
- Often yes — downstream sensors are cheaper parts and usually easier to access than upstream sensors.
- Can I ignore this code?
- You can drive indefinitely with no symptoms, but you will fail emissions inspection.
Related Repair Guides
If your vehicle has triggered P0161, these DIY repair guides may help: