[tjthorson]

I realize that this a thread that wont seem to die....

So.... Just from reading the thread - it is pretty easy to put together.

Red should have 12v - black to ground.

The pink wire is a pressure switch signal. So - when red has 12v, and the pump is pumping - when the system achieves 5psi (locker engaged) - the switch closes and stops the pump and sends 12v to the pink. That pink wire then signals the ECM that the locker is locked - and the light on the dash stops flashing and lights up.

Turn off 12v from the red, pressure releases, etc...

By you guys "testing" and applying 12v to the pressure switch in reverse (pink wire) - you most likely fused or shorted that switch. Which then means, applying 12v correctly to the red wire, all you hear is the "click" because the pressure switch cannot activate the pump any longer....

I havent pulled one apart myself - but I bet thats how it works... And why some of you indeed have dead pumps now.... You could probably replace the pressure switch part (if its serviceable) and it would work again...

Clear as mud?

[jay4554]

TJ ... you're the man ... I like coming back and bring this back from the dead... ha ha ... j\k i'll let it die

[gprguy]

Hate to be the one to dredge this up again, especially as my first post, but I registered just to post this.. This thread seems to have the most info about the Rubicon electric pumps that I've found, but there's still a lot of conflicting information.

Here's what I've figured out so far. I've taken the locker pumps out of my 2005 LJ Rubicon and am working to transplant them into my 2001 XJ (which also has my Rubicon axles now). I've also got a second 2005 LJ Rubicon with it's locker pump system intact that I can test against, but haven't gotten in that deep so far.

The pink and green wires - they appear to be a red herring. They are spliced together inside the wire loom before the first connector. They are the middle pin in the connector. Problem is on the Jeep side of the connector, the middle pin is unconnected. My guess is these motors are from some other application where the pink/green wires come into play.

Is there a pressure switch? I am not sure, but I am thinking yes. When the pump is running under no load or a slight load (it's output is either open or slightly blocked with my thumb) it's drawing about .45 amps. If I totally block the exhaust causing the pump to stop, it drops to .21 amps. It sounds to me like the pump is stalling, but if that were the case wouldn't the amperage rise, not drop? I am not sure what is drawing the .21 amps though. Another possibility is the pumps are stalling, but they are some kind of electrical motor that tolerates stalling without the current draw going through the roof. Not even sure if something like that exists, I'm not an EE...

I think I am going to throw together a small harness so I can test how much amperage our stock rubicon's pumps draw when being driven by the stock switch and all.

It does seem that if I get the pump up to pressure and stop/stall it with my thumb, then remove the power source, pressure is lost. So the idea that the computer turns off the pump once the front axle locks (vs it having an internal pressure switch) doesn't seem to hold water.

Oh, and from reading the FSM, it says specifically that the signal that switches the dash indicator lights from flashing (lock in progress) to solid (locked) is the axle switch, nothing on the pumps themselves.

I'm probably putting way more effort into this than I should, but hopefully it will help someone out in the future..

[gprguy]

Ok, that didn't take as long as I expected.

I tested our stock 2005 LJ Rubicon by putting an ammeter in the red power line to the locker pump.

Axle lock switch off - no power (duh).

Axle lock switch on, dash indicator flashing - pump runs and draws up to .55 amps until it stops. Then it draws about .21 amps. Locker is not engaged at this point but the pressure is there trying to engage it.

Move the rear wheel slightly to cause the locker to engage - pump runs another quick second when the locker pops into engagement which causes the amps to rise to .45-.55 again, and then drop to .21 amps, where it remains as long as the switch is engaged. Dash indicator goes solid (getting a signal from the switch on the axle pumpkin indicating a lock).

Turn locker switch off - amps drops to 0 as power is removed from the pumps. Dash indicator starts flashing until rear wheel is moved a bit to cause the locker to disengage, at which point the light goes out.

So that was pretty long winded, but I wanted to save someone else the effort in the future.

Short version: Hook the black to ground, the red to your switch or however you want to control the locker, and ignore the pink and green wires - they're not applicable in a Rubicon application. The pump has power to it the entire time the locker is engaged. Whatever it does (pressure switch, stalling out) I have no idea, but whatever it is that's how the stock Rubicon setup works so it must be fine. The axle switches on the pumpkins are just indicators for the stock computer.. Hook them up to indicator lights if you want, but they don't get wired directly into the pumps in any way.

[camper49]

I read this topic over a year ago when I was looking for instructions for the rubicon air pump install. I took the original and easy method described by paul tyler...red power and black ground. I wrote a long essay about my jeep build and included the following in my post....

I found a used rear dana 44 from a '03 rubicon TJ and purchased it shortly after I bought my TJ. I made this my first parts purchase before I spent all my modifications budget. It was in good condition with disc brakes, factory 4.10 gears, and the factory air locker. It didn't come with a locker air pump so I needed to purchase that as well. I ended up ordering one from the jeep dealer. I didn't know if I would have to buy the pumps as a pair but my friend at the parts counter had no problem ordering just one pump.


The pump is usually installed with a second pump for the front rubicon axle. I'm not sure how the factory computer plays into the wiring flow of two pumps. There are several wires leading from the pump I bought....a black ground wire, two red power wires that splice into one, and a pink wire and green wire that splice into one pink wire. All of these flow into a factory three wire plug....black, red, pink. I had read on the forum that all I needed were the red and black wires. I set the pump on the front fender by my battery and used some small jumper wires. I jumped the red and black plug blades to my battery and the pump began to whir. It has an internal switch that shuts down when approximately 5 psi is reached at the locker diaphragm. I put my finger over the output nipple and the pump shut down.

Below is a picture of the dana 44 locker when I was cleaning up the swap axle....you can see the brass air line nipple goes through the casting. It connects to the short rubber hose inside the pumpkin. There's a diaphragm that gets pressurized and engages the locker. The rear locker also has a limited slip feature that works without any pump pressure. Notice the pigtail harness hanging over the axle tube.


The differential pumpkin has a two wire pig-tail/switch sticking out near the passenger tube. I don't exactly know how it works. The switch senses when the air locker engages and closes a simple circuit. I purchased a mopar wire harness with the correct matching factory plug and a length of 3/16 vacuum line, all wrapped in plastic wire loom. The harness is only long enough to reach the factory rubicon center skid where the pumps are normally mounted. I'm going to run the two wires to a simple indicator light.


I won't be installing all this like it comes factory. I will be the only driver of my jeep and I don't need any safety features to restrict using the locker to only 4wd low range. I looked at some expensive rocker switches but decided to pass on a $20 switch and went with a cheap one from the local parts store. I bought a couple and threw one in the tool box. I added a simple indicator light. I don't know very much about electrical circuits. The short pump wire harness is all small gauge wire, so I hope the pump doesn't pull a lot of current. I already had some 18 gauge utility wire and some old in-line fuse holders. I made this install with a guess and a prayer. I don't claim it is a smart or correct install.





I would have liked to use the switch panel in the center console, but I didn't buy the correct style switch. I decided to make it easy. I can reach the rocker switch while driving and I can see the switch and the indicator light from my normal driving position by looking down through the steering wheel.


When the rocker switch is on, it glows red. When the pumpkin switch circuit is closed, the green indicator light glows.



I mounted the air pump on the inside fender under the brake master cylinder. The pump came with some small rubber grommet/isolators that I modified slightly to isolate the pump vibration from the sheet metal. It should stay relatively dry and undisturbed in this location. Normally the pump is mounted to a tray under the center of the rubicon near the transfer case. I don't know exactly what the tray looks like. I also don't have the matching plug body so I cut the pump plug off and left the pink wire unused. I have 12 volt power coming from the dash switch to the red wire. There's a existing ground screw forward near the driver headlight where I ran the black wire.


It may be a little confusing in the above photo because of the existing hoses and wires near the air pump. You can take another look at the first picture in this section. Five pump wires go into the black heat shrink, but only two (red and black) come out. I hope you see two rubber hoses coming off the pump body. The hose closest to you delivers about 5 psi to the rear locker. I had a length of 3/16 fuel line that was long enough to go unspliced all the way back to the rear differential. I figured the fewer splices I have, the fewer places to look for air leaks. The hose underneath where you see a little of the plastic nipple is only about 9-10 inches long and sticks basically straight up. That's the intake/vent hose.


....how I mounted the pump from the underside of the driver fender well....a slice of rubber sheet to further isolate the pump vibration.....


I don't know how to make a proper wiring schematic. I made this drawing to explain what I did. I don't think the pump pulls much current. It only runs for a few seconds. I didn't bother with a relay in the circuit. If someone who understands electric circuits wants to tell me what else I need to show, I can revise the drawing. I don't want someone else to damage their jeep based on my "instructions".


see more in the next post...

[camper49]

continued from above....

The next picture shows the factory pigtail coming out of the passenger side of the pumpkin. The harness I bought has the matching two wire plug. The air hose nipple is just behind where the pigtail/switch comes out of the casting.


I picked up some larger diameter wire loom at lowes and ran the two wires and the air hose from the rear over to the driver frame rail. You can see it ziptied to the sway bar. The two wires from the harness weren't long enough to reach the firewall, so I spliced in more about half way up the rail. The loom ends under the firewall where the 3/16 rubber hose runs to the pump, while the two wires run to the dash light and on to the battery.


I've used the locker in the woods and it works fine. The pump only runs for a second or two and then the green indicator light comes on to tell me the locker is engaged. The pump shuts down and holds pressure. I don't think it had to switch back on to re-pressurize the diaphragm but I may not have noticed while I was crawling around in the woods. I ran with some fellas a few weekends ago with the locker on for 15-20 minutes at a time. When I turn the locker off, the green light goes out. I never had any problem.

....one year later, everything still works fine.

[paultyler]

Originally Posted by gprguy

Short version: Hook the black to ground, the red to your switch or however you want to control the locker, and ignore the pink and green wires - they're not applicable in a Rubicon application. The pump has power to it the entire time the locker is engaged. Whatever it does (pressure switch, stalling out) I have no idea, but whatever it is that's how the stock Rubicon setup works so it must be fine. The axle switches on the pumpkins are just indicators for the stock computer.. Hook them up to indicator lights if you want, but they don't get wired directly into the pumps in any way.

I agree. That is exactly how mine is set up in my Jeep. It has been working fine for almost two years.

Camper49: Great job getting the "on-indicator" light to work. I just cut those wires off. But I like the way you did it. As an alternative to buying the wiring harness to make a separate on-indicator light , I just used on/off switch that has a light built in. If the locker is on, the light on the switch is on.

[mudb8]

I've had mine completely torn apart....

the nipple got busted off and was left unused for a couple years. the pump and motor were pretty dirty and the magnet had come unglued from beating on it... it does have a built in regulator, the pink wire isn't even hooked up as was mentioned abouve by someone, I figured i pulled it out when i disconnected the wireing...

heres a few pics of my quick fix.... I didn't actually get a good pic of the regulator, it's what is under the square cover held in with two screws and has two oring seals in the bottom. the pump is a plastic piston on a offset bearing to act as a crankshaft...






heres how i fixed the nipples...

5/32 bit and brake line tubing.

[BaddAndy]

I just installed 2 Rubi axles in my TJ. I know to hook Red to power, Black to ground for the pumps. If I hook pump Pink to Red on the diff and Black from the diff to a grounded dash light, will I get an illumination? This seem to only be the positive indiction of locker engagement.

[gprguy]

I can see how that would work, but it's not how it is wired from the factory, so you may be playing with fire there so to speak. Pink is unused from the factory, and you'd run a normal 12v + wire to the diff, then back from the diff to your indicator light.

[BaddAndy]

Originally Posted by gprguy

I can see how that would work, but it's not how it is wired from the factory, so you may be playing with fire there so to speak. Pink is unused from the factory, and you'd run a normal 12v + wire to the diff, then back from the diff to your indicator light.

OK, I now understand what you said about the pink midddle pin in the 3 pin connector not going to the jeep side. Now, what harness, or where does the power going to the axles come from, for the positive lock indication? I can't find a wiring diagram anywhere on the stock locker system.

[gprguy]

Originally Posted by BaddAndy

OK, I now understand what you said about the pink midddle pin in the 3 pin connector not going to the jeep side. Now, what harness, or where does the power going to the axles come from, for the positive lock indication? I can't find a wiring diagram anywhere on the stock locker system.

I honestly didn't look since the axle switches don't directly actuate the dash lights anyway - they just serve as inputs to the PCM and the fancy factory switch since it can make the lights be on steady, flash slow (locking) or flash fast (error). I can say they must be constant hot since the dash lights work regardless of the ignition state. There is a wiring diagram in my 2005 FSM, but it's not completely straightforward since it does integrate with the PCM.

FWIW, I've got Rubicon axles in my XJ, and I haven't hooked up the locker pumps yet (still have to build a bracket). But my plan is to run a pair of two LED contura switches which will turn on the pumps, and then run another 12v lead up through the axle switch and back to the second LED on the contura switch to indicate if they are actually engaged. The power draw for that circuit will be minimal to say the least.

[BaddAndy]

Looks like I'll be doing something similar. I want indication that the pumps have power and positive locker.

[gprguy]

If you don't already have the switches, I got mine from www.otrattw.com - part # V1DAF66B plus a rockers that say front and rear locker.

[BaddAndy]

Originally Posted by gprguy

If you don't already have the switches, I got mine from www.otrattw.com - part # V1DAF66B plus a rockers that say front and rear locker.

OOH, this is gonna get expensive!