Service 4WD light

B

BlueRubicon

Caught the Bug
Well, it is official. I hate the new JL. All this electronic bs they put on these things to appease the idiots. As we know, transfer case is mechanical so you CAN get it in 4H or 4L no matter what. However, if the indicator lights on your dash where it shows 2H 4H 4L, do not light up when in 4L, you cannot use your lockers. This has been happening to me for past three days and I am fucking over it. The non sense with these new Jeeps is absurd. Fortunately out here in Moab, the grip is so extreme, most the trails I have been on I can do in 2H or 4H no lockers needed. (Hells Revenge, Poison Spider) However I am going on some extreme trails and need to be able to use lockers if required. This fucking blows. Mind you it is intermittent, but it is adding stress to my vacation. FCA...you suck balls!!
 
That sucks! Sorry to hear that. Hopefully it will act right when you need it to. Are you gonna take it to the stealership when you get home? I’ll be curious to hear what they say about it. Fucking electronics, they are putting way to many of them in cars these days.


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BlueRubicon said:
Well, it is official. I hate the new JL. All this electronic bs they put on these things to appease the idiots. As we know, transfer case is mechanical so you CAN get it in 4H or 4L no matter what. However, if the indicator lights on your dash where it shows 2H 4H 4L, do not light up when in 4L, you cannot use your lockers. This has been happening to me for past three days and I am fucking over it. The non sense with these new Jeeps is absurd. Fortunately out here in Moab, the grip is so extreme, most the trails I have been on I can do in 2H or 4H no lockers needed. (Hells Revenge, Poison Spider) However I am going on some extreme trails and need to be able to use lockers if required. This fucking blows. Mind you it is intermittent, but it is adding stress to my vacation. FCA...you suck balls!!
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Too bad there isn’t a kill switch for the JL


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Damn that bites.

Sounds like a good excuse to get 60s with air lockers. Lock em up when you want.
Get some JKS disconnects too, for when the sway bar wont do its thing either.
 
Did you make sure to disconnect your locker wiring from the axle when you installed your lift? If not, you more than likely damaged it at the plug and now you're getting the intermittent problem that you're seeing.
 
wayoflife said:
Did you make sure to disconnect your locker wiring from the axle when you installed your lift? If not, you more than likely damaged it at the plug and now you're getting the intermittent problem that you're seeing.
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[emoji1312]

So, trying to be a good friend I installed a lift on my buddy’s JL and forgot to disconnect the locker wiring. He had the same exact issue as you are describing. The dealer narrowed it down to the harness and wanted to charge about 700 to replace. I convinced my friend to order the harness for 100ish and we replaced in about 45 min.


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wayoflife said:
Did you make sure to disconnect your locker wiring from the axle when you installed your lift? If not, you more than likely damaged it at the plug and now you're getting the intermittent problem that you're seeing.
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Yes, I unplugged FAD when I did the lift. That was a year ago and never experienced this issue. I am pretty sure it is either FAD switch or plug. I was on 'Top of the World' yesterday, and experienced same problem, however I notice that a good jolt would activate the 4L light and I could than use my lockers. I didn't need them but they were available. I am getting the Tazer Mini when I get back to Pa,, and will order RCV fad delete axle. Sucks because I just put in the FAD RCV axles.

I see on the Tazer options you can disable a whole bunch of these BS warnings on the JL.
 
BlueRubicon said:
Yes, I unplugged FAD when I did the lift. That was a year ago and never experienced this issue. I am pretty sure it is either FAD switch or plug. I was on 'Top of the World' yesterday, and experienced same problem, however I notice that a good jolt would activate the 4L light and I could than use my lockers. I didn't need them but they were available. I am getting the Tazer Mini when I get back to Pa,, and will order RCV fad delete axle. Sucks because I just put in the FAD RCV axles.

I see on the Tazer options you can disable a whole bunch of these BS warnings on the JL.
Click to expand...

Didn't say anything about the FAD. Being that you're having a locker issue, that's the wire you need to be focused on. IF you unplugged it as well when installing your lift, you should make sure that you have enough slack in the wiring harness at a full flex. If you don't, that's your problem.
 
wayoflife said:
Didn't say anything about the FAD. Being that you're having a locker issue, that's the wire you need to be focused on. IF you unplugged it as well when installing your lift, you should make sure that you have enough slack in the wiring harness at a full flex. If you don't, that's your problem.
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Yes Eddie, I unplugged everything when doing lift. I also verified all wiring, brake lines, etc. have the necessary slack. It isn't the lockers. Lockers will function fine when the ECU see's that the vehicle is in 4L. If putting transfer case in 4L, but 4L light does NOT illuminate, ECU does not see you are in 4L and will NOT allow you to lock the lockers. It will give message saying 'Put in 4WD LOW', when activating locker(s). You can drive around for half hr with transfer case in 4L, but unless little light on dash at 4L is illuminated, the FAD does not engage axles. Once vehicle is jolted or whatever, and 4L light illuminates, everything functions fine. So I am pretty sure it is either the FAD switch, or the connection to it. If that fork in the FAD unit does not slide the collar over, you have no front axles.
 
Eddie, the video you posted after you had the Pro Rock installed on your JL, referring to the ECU not allowing you to use lockers or sway bar disconnect is very similar to my condition. Obviously a little different because your fad is gone, but the ECU does not recognize your in 4L, because your indicator lights weren't on. Same problem here. I removed my sway bar disconnect a long time ago, and have the EVO manual one. But I have the light all the time about the sway bar. I just ignore it. You were seeing similar issues. The Tazer fixed it by disabling. I will still need to get the solid right side RCV in order to use the front axle.

Thank you for responding to me in PM yesterday, and thank you for you very informative videos as you deal with these issues yourself. And especially thank Cindy for her Superb video work. I know she works hard and does a fantastic job. Your video quality and narrative is the best on Youtube
 
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Update: JL was at the dealer today. After explaining thoroughly to service writer over the phone, he had to stop me because he did not know what the FAD was. After explaining it, he said in all his years he has never heard of it. In the interim, I typed detailed issue and left in the Jeep for the Tech. When dropping off the service writer begins by telling me that it is probably 'normal' and that he talked to the techs and none of them heard of the FAD. I grimaced and simply said, I left detailed description for the tech and I got out of there before getting arrested. Needless to say all day I had knot in my stomach.

He called late afternoon saying it was done and I could pick it up. When I asked if it was fixed, he said they found bad wiring to the plug for the front axle disconnect. He didn't elaborate except to say tech repaired it. By the time I got there to pick up, techs and writers gone.

My RCV passenger side (solid) axle and FAD delete plate is on the way, and I have Tazer Mini sitting next to me. As soon as axle is here, FAD is gone and Tazer is installed.
 
BlueRubicon said:
Update: JL was at the dealer today. After explaining thoroughly to service writer over the phone, he had to stop me because he did not know what the FAD was. After explaining it, he said in all his years he has never heard of it. In the interim, I typed detailed issue and left in the Jeep for the Tech. When dropping off the service writer begins by telling me that it is probably 'normal' and that he talked to the techs and none of them heard of the FAD. I grimaced and simply said, I left detailed description for the tech and I got out of there before getting arrested. Needless to say all day I had knot in my stomach.

He called late afternoon saying it was done and I could pick it up. When I asked if it was fixed, he said they found bad wiring to the plug for the front axle disconnect. He didn't elaborate except to say tech repaired it. By the time I got there to pick up, techs and writers gone.

My RCV passenger side (solid) axle and FAD delete plate is on the way, and I have Tazer Mini sitting next to me. As soon as axle is here, FAD is gone and Tazer is installed.
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Its because you said FAD not front axle disconnect... :crazyeyes:

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BlueRubicon said:
Update: JL was at the dealer today. After explaining thoroughly to service writer over the phone, he had to stop me because he did not know what the FAD was. After explaining it, he said in all his years he has never heard of it. In the interim, I typed detailed issue and left in the Jeep for the Tech. When dropping off the service writer begins by telling me that it is probably 'normal' and that he talked to the techs and none of them heard of the FAD. I grimaced and simply said, I left detailed description for the tech and I got out of there before getting arrested. Needless to say all day I had knot in my stomach.

He called late afternoon saying it was done and I could pick it up. When I asked if it was fixed, he said they found bad wiring to the plug for the front axle disconnect. He didn't elaborate except to say tech repaired it. By the time I got there to pick up, techs and writers gone.

My RCV passenger side (solid) axle and FAD delete plate is on the way, and I have Tazer Mini sitting next to me. As soon as axle is here, FAD is gone and Tazer is installed.
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I deal with this daily with my writers. I have to go into detail about what I repaired sometimes cause they are clueless, then they still explain the repair to the customer wrong.

Glad you got it fixed in the end even if your writer is a dumbass
 
I stopped into the shop today, and talked to the tech myself. ECM is in the rear of the Jeep by the fender, which sends the voltage to the FAD. Voltage WAS present out of the module. There is a connection in between the rear of fuel tank and the front. Those also had voltage present. He opened up the loom and ran a new wire from last connection to FAD connector. I asked if the bad wire could of been caused by 'flex', and he said he was not able to determine exactly where wire was bad. This is satisfactory and I was very appreciative to the tech.
 
I have the same intermittent issue. I've come to notice the sequence of warning lights is:
vehicle stability comes back on
service 4WD
swaybar - which then stays on
and lastly the 2/4 H/L indicator goes dark, changing from low to high or 2wd changes nothing.
stop, shut off, restart, everything is back to normal, until I go into 4WD again (H or L)
sometimes I can drive in 4H and or 4L with no issues. it has happened when wheeling up a hard trail and on basically flat and smooth-ish ground.
swaybar disconnect on or off, lockers on or off. Cannot force symptom at will.

super frustrating and it has left me without lockers when I needed them.

2 different dealers and gone over connections myself.. I have a lift and both dealers are saying return it stock to troubleshoot any further. the lift has been on for a few years before the issue started.
 
bikenutty said:
I have the same intermittent issue. I've come to notice the sequence of warning lights is:
vehicle stability comes back on
service 4WD
swaybar - which then stays on
and lastly the 2/4 H/L indicator goes dark, changing from low to high or 2wd changes nothing.
stop, shut off, restart, everything is back to normal, until I go into 4WD again (H or L)
sometimes I can drive in 4H and or 4L with no issues. it has happened when wheeling up a hard trail and on basically flat and smooth-ish ground.
swaybar disconnect on or off, lockers on or off. Cannot force symptom at will.

super frustrating and it has left me without lockers when I needed them.

2 different dealers and gone over connections myself.. I have a lift and both dealers are saying return it stock to troubleshoot any further. the lift has been on for a few years before the issue started.
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Eliminating the FAD, installing one piece pass side axle and installing Tazer, has elliminated most warning lights while wheeling. Every once in a while will still get a warning light for something transmission related, but goes away. I don't think for a moment that down the road other warnings won't appear. The ECU controls everything and if it see's something it deems wrong, it will send out warning or worse shut something down.
I miss vehicles with no ECU's, and having a carb and distributor.
 
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BlueRubicon said:
I miss vehicles with no ECU's, and having a carb and distributor.
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Not me... Modern fuel injection is great, to get the same horsepower from classic engines as todays modern injected engines they ended up being maintenance heavy and short lived. I don't miss flooded engines, timing issues, poor gas mileage, hard starts, vapor lock, Etc. Also todays fuel is not optimized for operating in carbureted engines. Gasoline manufactures have reduced the vapor pressure of gasoline because vapor pressure doesn't matter with fuel injection.
 
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