1988 O2 sensor pinhole order

[Randy V]

Hi,
I have a 1988 Bronco II and I'm having trouble with the O2 sensor connector. The wires got ripped out of the connector (I still have the end of the connector) and I'm not sure how to rewire it. (It's a 3 wire not 4 wire) Is there a wiring diagram or an image for the back of the connector out there? Like what wire goes into which pinhole. (I don't want to mix up the wires).
I have looked into buying a new connector and splicing into the wires but I can't find a replacement 3 wire connector that will connect to the O2 sensor.
My wires are:

• Blue/ White
• Black/ Red
• Orange/ Yellow

I replaced the old O2 sensor with an exact OEM (Bosch 3 wire).
Any help would be appreciated.
Thanks

 

[alwaysFlOoReD]

Can you post a pic?
What engine?
I'm assuming engine side of the connector if you replaced the o2 sensor.
I don't know if I can help but I think the info I requested might help others answer you.

 

[Randy V]

It's a 2.9 liter
4x4
Automatic
XL
No AC

 

[JerryC]

You can buy a new O2 connector for less than twenty bucks. AZ and Napa both list them.

 

[86fordbroncoii]

For 3 Wire sensors, polarity doesn't matter, meaning 12v+ and GND are interchangeable. That leaves you to the signal wire that runs to the ECM. I would try to trace one of the three wires that trace back to the ECM connector through the passenger side of the firewall. These wire colors are unusual, as usually you have a Dk Green/Purple (Signal), Orange/Black, and Black/Lt Green. EDIT-Also as stated above, you can get replacement Bosch 3/4 Wire sensors from most if not all auto parts stores. The 4th wire is chassis ground.

 

[Randy V]

Thank you for the wiring diagram!
I have tried to get a replacement but I can't find a 3 wire with the connector that I have. The 3-wire that AZ sells isn't what I have, for what ever reason.

Also I'm still not sure which wire goes to which pinhole. On the Bosch O2 sensor there are two white wires and a black wire. (I'm not sure what each of the wires are.) Does anybody have a picture of the back of the O2 sensor connector?

 

[JerryC]

I'll try to remember to crawl under mine and take look after work .

 

[86fordbroncoii]

Thank you for the wiring diagram!
I have tried to get a replacement but I can't find a 3 wire with the connector that I have. The 3-wire that AZ sells isn't what I have, for what ever reason.

Also I'm still not sure which wire goes to which pinhole. On the Bosch O2 sensor there are two white wires and a black wire. (I'm not sure what each of the wires are.) Does anybody have a picture of the back of the O2 sensor connector?

View attachment 14686

If you can't locally find a connector/sensor combination that works for you, I would check with RockAuto as they have the more 'unusual' parts in supply (like hydraulic clutch lines for these trucks, if you ever need one). If not, 9 times out of 10 these universal sensors come with wiring diagrams. Like I said before, power and ground doesn't matter as long as one side has power, one side has ground, and follow back whichever wire goes to the firewall. If that still doesn't do it for you, hopefully you can find an 88 in a junkyard because most wire colors are as described in the diagram

 

[JerryC]

On mine, the black from the O2 goes to the blue/yellow. It seems to have a green wrapper that matches your picture.