The 4.6L Ford F150 and F250 Pickup comes equipped with 4 heated oxygen sensors (HO2S). This article contains the wiring diagrams of all 4 oxygen sensors.
RF Oxygen Sensor (O2S11) Wiring Diagram

RF Oxygen Sensor Troubleshooting Notes:
- The right front oxygen sensor is located on bank 1 and before the catalytic converter.
- Bank 1 is the bank of cylinders that houses cylinders #1, #2, #3, and #4.
- Bank 1 is located on the passenger side of the engine compartment.
- The right front oxygen sensor is also known as:
- HO2S11 (Heated Oxygen Sensor Bank 1 Sensor 1).
- Bank 1 upstream oxygen sensor.
- Right upstream O2 sensor.
LF Oxygen Sensor (O2S21) Wiring Diagram

LF Oxygen Sensor Troubleshooting Notes:
- The left front oxygen sensor is located on bank 2 and before the catalytic converter.
- Bank 2 is the bank of cylinders that houses cylinders #5, #6, #7, and #8.
- Bank 2 is located on the driver side of the engine compartment.
- The left front oxygen sensor is also known as:
- HO2S21 (Heated Oxygen Sensor Bank 2 Sensor 1).
- Bank 2 upstream oxygen sensor.
- Left upstream O2 sensor.
RR Oxygen Sensor (O2S12) Wiring Diagram

RR Oxygen Sensor Troubleshooting Notes:
- The right rear oxygen sensor is located on bank 1 and AFTER the catalytic converter.
- Bank 1 is the bank of cylinders that houses cylinders #1, #2, #3, and #4.
- Bank 1 is located on the passenger side of the engine compartment.
- The right rear oxygen sensor is also known as:
- HO2S12 (Heated Oxygen Sensor Bank 1 Sensor 2).
- Bank 1 downstream oxygen sensor.
- Right downstream O2 sensor.
LR Oxygen Sensor (O2S22) Wiring Diagram

LR Oxygen Sensor Troubleshooting Notes:
- The left rear oxygen sensor is located on bank 2 and AFTER the catalytic converter.
- Bank 2 is the bank of cylinders that houses cylinders #5, #6, #7, and #8.
- Bank 2 is located on the driver side of the engine compartment.
- The left rear oxygen sensor is also known as:
- HO2S22 (Heated Oxygen Sensor Bank 2 Sensor 2).
- Bank 2 downstream oxygen sensor.
- Left downstream O2 sensor.
Where To Buy The Oxygen Sensor And Save
The best place to comparison shop and get an idea of how much your Ford pickup's oxygen (O2) sensor cost (and how much you can save) is here:
Not sure if the above oxygen (O2) sensor fits your particular Ford pickup? Don't worry, once you get to the site, they'll make sure it fits by asking you the particulars of your vehicle. If it doesn't fit, they'll find you the right one.
More Ford 4.6L, 5.4L Diagnostic Tutorials
If you enjoyed and/or found this ‘How To’ article helpful, I have written several more Ford 4.6L, 5.4L specific test articles. You can find them all in this index: Ford 4.6L, 5.4L Index Of Articles
Here's a small sample of the articles you'll find there:
- How To Test The Fuel Pump -No Start Test (Ford 4.6L, 5.4L).
- How To Test The Crankshaft Position Sensor (Ford 4.6L, 5.4L).
- How To Test Ford Coil-On-Plug Ignition Coils 4.6L and 5.4L V8 Engines (at: easyautodiagnostics.com).
- How To Test The Throttle Position Sensor Ford, Mercury, Lincoln 4.6L and 5.4L Engines (at: easyautodiagnostics.com).
- How To Test The FORD MAF 4.2L, 4.6L, 5.4L Round Air Filter Canister Assembly MAF Sensor (at: easyautodiagnostics.com).
- How To Test Ford MAF Sensors Using a Multimeter (at: easyautodiagnostics.com).

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