Rubicon Locker Mystery Mod

AndyG

Because some other guys are perverts
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I hooked my buddy Clinton up with a clean, stock 2004 Rubicon auto.

The stock 4 wheel drive switch does not work at the transfer case thus no light. The dash function test showed the light works at the cluster, no bulb issue. (Hold odometer reset and turn key on)

So, what they did was put a switch by the lockers that makes the PCM think the Jeep is in 4 lo and the lockers work once you hit it.

Never seen this and not sure how they did this and wonder what they used to signal
to the pcm to allow the locker function…my thinking would be the switch opens the loop as the t/c switch is designed to do (it’s closed at rest) but if so, why no 4wd light? Seems the pcm would light the dash up but I don’t know the circuitry.

Ultimately we will do the locker mod but we want the light regardless. The locker lights work correctly.

I’m thinking we still need a good t/c switch and then have to sort this out- just trying to get ideas in advance.

Thanks
Andy
 
There are a few ways of bypassing the factory requirements for locking the axles, and I’m pretty sure doing it this way doesn’t light up the 4WD switch.

Why I can’t link text on my phone, I dunno, but here you go: https://wranglertjforum.com/threads/rubicon-locker-bypass.68747/

What makes you think a bypass isn’t already done? It sounds like that’s exactly what the switch is doing. And it could mean that the axles could be locked even while not in 4WD.
 
Way back, I had mine wired to an “enable” switch so I could use them in 4hi. That mod didn’t have anything to do with the 4wd indicator in the dash. I don’t believe the locker bypass is causing your issue. Perhaps the switch simply went bad, and rather than fix it, they installed a switch to fool the pcm into letting the lockers come on.

Check out the wandering trail site for various ways on how to bypass the locker switches and pcm logic.
 
Thanks guys- I really can’t answer the above questions because the jeep went home with him and I didn’t get to go through every scenario but both of the above posts will help me.
 
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I hooked my buddy Clinton up with a clean, stock 2004 Rubicon auto.

The stock 4 wheel drive switch does not work at the transfer case thus no light. The dash function test showed the light works at the cluster, no bulb issue. (Hold odometer reset and turn key on)
Any time we've had the dash light prevent the locker switches from working, only a scant few of those times have been a bad mode switch on the t-case. All of the other times it has been due to improper software loaded into the PCM. Don't assume the light doesn't work due to the mode switch. Biggest clue is the PCM will have an aftermarket sticker on it of some sort.
So, what they did was put a switch by the lockers that makes the PCM think the Jeep is in 4 lo and the lockers work once you hit it.

Never seen this and not sure how they did this and wonder what they used to signal
to the pcm to allow the locker function…my thinking would be the switch opens the loop as the t/c switch is designed to do (it’s closed at rest) but if so, why no 4wd light? Seems the pcm would light the dash up but I don’t know the circuitry.

Ultimately we will do the locker mod but we want the light regardless. The locker lights work correctly.

I’m thinking we still need a good t/c switch and then have to sort this out- just trying to get ideas in advance.

Thanks
Andy
More likely is they have done as Mike stated, just done the bypass to get them working again.
 
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Any time we've had the dash light prevent the locker switches from working, only a scant few of those times have been a bad mode switch on the t-case. All of the other times it has been due to improper software loaded into the PCM. Don't assume the light doesn't work due to the mode switch. Biggest clue is the PCM will have an aftermarket sticker on it of some sort.

More likely is they have done as Mike stated, just done the bypass to get them working again.

Yes that’s what I’m thinking I’m going to start with testing the plug to see if it fires up the dash light-

The mod they did if they did one still uses the factory switch so it really didn’t accomplish everything

The dorman replacement switch didn’t do anything but I don’t have any confidence in aftermarket switches and I think I ran into that same problem so we’re going to pick up a Mopar switch if jumping the plug lights up the dash

Then do the locker mod where you’re grounded everything through independent switches

If I’m not making sense I am in pretty ridiculous pain this morning from some kind of sciatic deal and just trying to run on a construction company without going off the rails... Which it seems to want to do by itself

The PCM appears to be bone stock compared to my identical 2004 jeep tjr and his is a 2004 and they are both automatics
 
...I am in pretty ridiculous pain this morning from some kind of sciatic deal
Get yourself an inversion board Andy and use it when needed. They work by pulling the spine straight from the weight of your upper body pulling downward on it to help stop it from pinching nerves. I have a really bad back including occasionally really sciatica pain from injuring it 35 years ago and I finally bought one 25 years ago to help it which turned out to be a great decision. If I use it even semi-regularly my back usually stays in pretty good condition. They can help a lot with a sudden new back pain too, as in being able to walk again after using it a couple times. Mine is a quality Teeter brand and as old as it is it still looks like new and still works as well as it did when brand new. They really do help back problems.

Teeter.jpg
 
Get yourself an inversion board Andy and use it when needed. They work by pulling the spine straight from the weight of your upper body pulling downward on it to help stop it from pinching nerves. I have a really bad back including occasionally really sciatica pain from injuring it 35 years ago and I finally bought one 25 years ago to help it which turned out to be a great decision. If I use it even semi-regularly my back usually stays in pretty good condition. They can help a lot with a sudden new back pain too, as in being able to walk again after using it a couple times. Mine is a quality Teeter brand and as old as it is it still looks like new and still works as well as it did when brand new. They really do help back problems.

View attachment 514904

Got ya- thanks- gotta have some relief Jerry. Just stepped out of my truck and pinched a nerve- the joy of getting older.

After 40 you go to the Dr. and he comes in and says “lets close this door....”
 
Get yourself an inversion board Andy and use it when needed. They work by pulling the spine straight from the weight of your upper body pulling downward on it to help stop it from pinching nerves. I have a really bad back including occasionally really sciatica pain from injuring it 35 years ago and I finally bought one 25 years ago to help it which turned out to be a great decision. If I use it even semi-regularly my back usually stays in pretty good condition. They can help a lot with a sudden new back pain too, as in being able to walk again after using it a couple times. Mine is a quality Teeter brand and as old as it is it still looks like new and still works as well as it did when brand new. They really do help back problems.

View attachment 514904

I have a newer version of one of those Teeters and it helps a lot.
 
A few years ago I found a thread here and on other websites that I used as a guide. I cant remember exactly what pins I jumped but my factory switch still works as from the factory with restrictions. My front/rear switches that I installed will lock the axle under any circumstances. The locker lights on the dash work as intended (solid on when locked and flashing when switch position does not match locker condition). All wiring was done behind the factory locker switch.
 
A few years ago I found a thread here and on other websites that I used as a guide. I cant remember exactly what pins I jumped but my factory switch still works as from the factory with restrictions. My front/rear switches that I installed will lock the axle under any circumstances. The locker lights on the dash work as intended (solid on when locked and flashing when switch position does not match locker condition). All wiring was done behind the factory locker switch.

Thanks- that is exactly how both of mine work-

Not sure what has been done to this one- yet
 
I hooked my buddy Clinton up with a clean, stock 2004 Rubicon auto.

The stock 4 wheel drive switch does not work at the transfer case thus no light. The dash function test showed the light works at the cluster, no bulb issue. (Hold odometer reset and turn key on)

So, what they did was put a switch by the lockers that makes the PCM think the Jeep is in 4 lo and the lockers work once you hit it.

Never seen this and not sure how they did this and wonder what they used to signal
to the pcm to allow the locker function…my thinking would be the switch opens the loop as the t/c switch is designed to do (it’s closed at rest) but if so, why no 4wd light? Seems the pcm would light the dash up but I don’t know the circuitry.

Ultimately we will do the locker mod but we want the light regardless. The locker lights work correctly.

I’m thinking we still need a good t/c switch and then have to sort this out- just trying to get ideas in advance.

Thanks
Andy

HEY BUDDY!
 
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HEY BUDDY!
😊


120,000 miles

13,800.00

Perfect ready to roll or build to wheel and daily platform.

May get to do a thread on the little build we do-

If anybody is ever looking for anything in particular feel free to let me know and I’ll always keep my eyes open-


Andy