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Identify Harness Connector?

XJ-Mayhem

NAXJA Member
NAXJA Member
Location
San Jose, CA
I’m hoping to take the easy way out and have someone who knows these things like the back of their hand tell me what the connector goes to.

1990 4.0/AW4, I’m currently working through Cruisers list and cleaning all connectors/applying dielectric grease and I haven’t been able to figure out what this connector goes to. Came unplugged when I bought it. It’s not the MAP or CPS, those are already connected. It’s a 3 pin with only 2 wires in the A and B slot. Looks like red and white are the colors, but I forgot to clean it before the pic.

also, any options other than finding a JY harness to fix broken connectors on the harness side? As you can see, I have the MAP plug zip tied in place to hold it. Both TPS connectors are broken as well.


0bab9d4d_83dd_4b9d_995b_b6d25236ab7e_387154bfebf18a09322ca73e4e6508add76b3ebc.jpeg
 
Apparently there is a mod that was done at the dealership that hard wired the 02 Sensor into a new connector. THIS is probably the left over connector.


That would make a lot of sense as to why it doesn't seem to go to anything. Although seems like kind of a far stretch for the sensor cable.



I just spent time last night cleaning up and re-taping the O2, knock, and what I assume is coolant temp sensor down by the driver motor mount - I think I did think to myself at one point that it looked a little patched together. What was the advantage of doing this?



So... will either connector work for the 02 sensor then? I have a hunch I'm having O2 sensor issues, but will confirm for sure when my REM gets here... but I'd be curious to try plugging it into the old port to see if there's any difference.
 
Not the O2 sensor. The O2 sensor has 4 wires. But Hotwire is still on track. That's the CPS sensor. Same thing, end spliced together to eliminate the connector.

Feel around and/or use a strong flashlight to locate the harness on the CPS and follow it until you find where it spliced into the main harness.

My guess is the PO left the connector in order to change the CPS without having to cut wires and splice if done on the road.

The wires should be Violet/tracer and White/tracer.

I also responded in the other forum.
 
Weird, my CPS is connected to the connector that can be seen to the upper right of the image, zip tied to the harness that wraps behind the MAP. I've already traced that and disconnected and cleaned up the connection before plugging it back in.
 
Like I mentioned, I was trying to take the easy way out but it sounds like I'll have to start tracing back both the harness the CPS is currently plugged into and the mystery one here to find out more. Thanks for the help, I'll share what I find
 
Like I mentioned, I was trying to take the easy way out but it sounds like I'll have to start tracing back both the harness the CPS is currently plugged into and the mystery one here to find out more. Thanks for the help, I'll share what I find


I took a look at my '90 and that connector is sitting in the same exact spot as my CPS connection and the connector looks the same. The issue with this spot is that it sits very close to the exhaust manifold so Jeep installed two metal clips to hold the wire in place. One connects to the top of a head bolt and the other sits down by the bellhousing. This is supposed to keep the wire at a safe distance but I suspect the PO might have had a problem with these clips being bent and decided to move the connector to a more protected spot.


HTH
Todd
 
Weird, my CPS is connected to the connector that can be seen to the upper right of the image, zip tied to the harness that wraps behind the MAP. I've already traced that and disconnected and cleaned up the connection before plugging it back in.

OK I see it now. I'll have to look more closely at mine. Odd.
 
Well, here's mine. I can only find one connector like this and it's to my CPS. The Violet and White (with tracers) come from the engine harness. The Red and White go down to the CPS. Bear in mind that mine still has the C101 connector so your routing could differ.

TiQQOv8.jpg



Let's us know what you find out.
 
So it looks like it’s most likely the old CPS connector. The current CPS is plugged into a connector that then directly heads into the firewall and presumably straight into the ECU?
 
Well, that's where they normally go. I still have the C101 connector on my '88 so lot's of folks do this bypass to eliminate the extra connection.

Not so with your '90. Perhaps there was some other break/short in the wire somewhere?

Hopefully someone with '90 will chime in.
 
Oh interesting, I thought from the factory the CPS joined the main loom right there.



I still haven't done a good dig to really trace it, I just recalled that as I was working in that area the other day.
 
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