Identifying plugs in engine bay, passenger-side

[skyzero]

Ok so I'm just about done with the installing the fenders back on and putting the engine bay back in order. There are 3 open connections and I'm unsure of where they go. As luck would have it, my pictures don't show where they plug or if they were even plugged in before.

The previous owner had all kinds of wires running all over the place but these look like OEM ones. So maybe there are dealer options? I looked all over the jeep and I can't seem to find any open connections where these would go.

Tried looking online for pics of engine bays but can't spot anything similar. I did find a post or two in other forums with similar pictures that mentioned plugs 2 and 3 might be AC wiring. For reference, the jeep does have AC and it was working previously.

https://imgur.com/a/tcVFvxi

Any help would be greatly appreciated!

 

[machoheadgames]

So two of them are AC plugs and one is for 4X4 light. But, there are three types of AC: factory, dealer, and aftermarket. Factory was always hooked up to the factory wiring; i.e. the plugs you see. Dealer installed could go either way, depending on if they sourced parts from places like JeepAir (aftermarket) or Chrysler. From Chrysler they would have plugged it in. The aftermarket stuff some dealers used basically pulls power from an ignition power source in the glove box, and then uses it’s own simple wiring harness to go to the compressor and the AC drier on the fender.

So for the plugs:

1. Factory AC compressor plug-in. Looks like you have aftermarket AC that is bypassing the factory wiring with its own wiring. I bet if you look at the fuse box there is a random wire (typically blue) plugged in that is powering the entire AC system.

2. Looks like 4X4 light wiring. From the factory, it plugs into a jumper harness that runs down to the front axle to light up the dash light when the vacuum CAD engages after putting Jeep in 4Hi or 4Lo. Let me guess, this light doesn’t work?

3. Factory AC drier wiring. Looks like again, you are using aftermarket AC either installed by dealer or previous owner, and it is bypassing the factory wiring with its own wiring.

 

[skyzero]

Thanks again for the help, I really appreciate it!

I can rest easy knowing that I didn't inadvertently misplace a connection or left something unplugged. I didn't realize that aftermarket AC didn't have to use the same lines.

You're right. the 4x4 light doesn't work. I'll check on that and get it working now that I know what the plug is for.

 

[machoheadgames]

Thanks again for the help, I really appreciate it!

I can rest easy knowing that I didn't inadvertently misplace a connection or left something unplugged. I didn't realize that aftermarket AC didn't have to use the same lines.

You're right. the 4x4 light doesn't work. I'll check on that and get it working now that I know what the plug is for.

No problem, very common questions as most people aren’t accustomed to buying vehicles and finding random unused plugs all over the place.

As for the 4x4 light, it’ll help to figure out how that system is working currently before digging into the light. From the factory is the vacuum system. When the vacuum fork is slid over in 4WD, it pushes a button on a small continuity switch. The light’s ground goes out to the switch, other wire carries the light’s ground actually to ground. That harness being unplugged makes me think the previous owner may have swapped you away from the vacuum setup. That doesn’t mean you can’t make the light work, but you’d need to snip that plug off and rewire some wiring down to the transfer case and buy a transfer case switch if so.

Some pics of your front axle from behind would help to figure out if you still have the vacuum setup or not, and go from there.