Downstream O2 Sensor Wiring

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Aug 23, 2020 | 03:20 PM

johnnyo1986

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Downstream O2 Sensor Wiring

I bought a 1996 F350 460 cab chassis truck that appears to be a Cali emissions truck (3 O2 sensors and an OBD II) . The infinite wisdom of the previous owners was that unhooking vacuum lines, electrical connections and clipping the o2 sensors were all power adders. So far I've been lucky and found a ton of information and photos on here to get the wrongs righted, except for this downstream O2 sensor. They clipped the plug off what I can only assume is the correct 4 wire harness. I didn't know if anybody has a wiring diagram or know the correct wire colors so I can wire up a new connector. Thanks in advance for the help.

Aug 23, 2020 | 06:35 PM

torq'ta 5 8

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From: N.W. Alabama

maybe, bottom left of page
0996b43f8021dd65.gif (1000×1122)

Aug 23, 2020 | 09:50 PM

rla2005

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From: Kentucky

Heated Oxygen Sensor 21 is the designator for the third O2 sensor that monitors converter efficiency. And yes, it is on the bottom left of the diagram previously posted.