2005 Rubicon Front Locker Wiring

[dukegrad]

Hi folks- I noticed an issue w/ my front air locker where it was working but the indicator was still flashing on the dash. Crawled under front pumpkin and found the following:

• Short sensor and connector from diff to top of pumpkin seem fine.
• The wire coming from that top-of-pumpkin connector is ripped off about 18 inches from the top-of-pumpkin connector.
• So far, I haven't been able to locate the other end of that wire but I assume that it goes from that pumpkin connector back to the pumps mounted on the skid plate. Back there I did find a connector that is plugged in but there are no wires. My thinking is that at some point, the wires were ripped out of the connector itself near the pumps and torn off near the pumpkin.
• I think this wire is what tells the system the locker is engaged (hence why it would work but dash indicator would only flash and never turn solid)

Looks like that wire/harness might be 52104 603ab, but everywhere I've looked that seems to be discontinued. Any ideas before I get to splicing or other workaround?

Thanks!
-Eric

 

[Jerry Bransford]

Are you certain the front locker is actually working? The light won't go solid until the locker has actually locked. You must first drive it a short distance while giving the steering wheel a slight turn or to like an S-turn to the two halves of the locker can rotate at different rpms so they can lock together.

Has any work been done recently inside your front axe?

 

[dukegrad]

Great question, Jerry! Short answer is 'sort of'. I have another issue I'm fixing at the same time as this... the plastic nipple on the front locker pump (that connects to the hose) broke off a while back. At the time I did a JB Weld quick fix that lasted probably longer than it should have, but inevitably has developed a small leak. So, long story short.... front locker pump works fine and builds pressure at the output, the nipple on the pump output has developed a leak (fix in progress) which has led to the front locker itself being intermittent. No axle or diff work has been done since the locker was previous working fine.

So, long story short... at minimum I know I need to fix a nipple leak and replace a wire Those will probably/hopefully solve the issues.

-Eric

 

[sierradmax]

Those supply nipples can be brittle. If you are unsuccessful with JB weld, Rubicon Resurrection has used pumps reasonably priced.

https://rubiconresurrection.business.site/?utm_source=gmb&utm_medium=referral
As for the locker sensor function, yes, the sensor wiring goes from the plunge type sensor on the differential to another connector at the skid. While the below is listed as "rear", I know the sensor connectors, both fro the front and rear, are the same. The connector at the skid, I do believe is the same, too.

https://www.ebay.com/itm/3041450496...d=link&campid=5337789113&toolid=20001&mkevt=1

 

[dukegrad]

Thanks for the link above- and a shout out to Rubicon Resurrection! Great customer service, great price, fast shipping. Back in business with a new homemadeharness and new-to-me pump.

For anyone wondering what OEM connectors are used on our Rubi pumps/diffs, it’s Aptiv (formerly Delphi) Apex 2.8 series. I bought the male pins from Mouser and they are identical to the OEM ones. All the connectors and pins can be found in that series should you need to repair any connections. Crimpers can be found on Amazon.

While I was at it, I also tracked down the infamous flashing locker dash lights on my rig (lockers engaged but both front and rear lights flash, never solid). Turns out, my issue was from a 3yr old fix of a broken ignition pin assembly. If you or PO replaced that part (common issue it seems) you may want to check the length of the plastic pin on the new one. Turns out the brand new one I installed 3yrs ago had a plastic pin that was about 1/8” shorter than original one. It wasn’t making contact with key-in switch on ignition switch assembly. Simple fix to swap plastic pins since I still had the old part in a parts bin, but what a PITA! And on a brand new part, no less! Lockers and lights are all now working as they should. Woot!

 

[sierradmax]

That must have taken some serious time and effort in troubleshooting. They're simple machines but have millions of parts.