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Home >> Mercury >> 1997 >> Sable V6-3.0L VIN U >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Oxygen Sensor >> Locations >> OBD-II Heated Oxygen Sensor Numbering Convention
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OBD-II Heated Oxygen Sensor Numbering Convention

HO2S Locations:





The first oxygen sensor in cylinder bank #1 is numbered HO2S11.
The second oxygen sensor in cylinder bank #1 is numbered HO2S12.
The first oxygen sensor in cylinder bank #2 is numbered HO2S21.
The second oxygen sensor in cylinder bank #2 is numbered HO2S22.

- Cylinder bank number one is the bank that contains number one cylinder.
- If a V-6 or V-8 vehicle only uses one downstream Heated Oxygen Sensor (HO2S) it is numbered HO2S12, even if it uses two upstream HO2S.
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