01 LX 470 - Center Diff Stuck in Locked Mode (2 Viewers)

[tyl3rd]

Hey all,

Went wheeling this weekend before doing some camping, turned on the center locker for a particularly steep area, everything engaged fine, but after word the center diff light and VSC light would not turn off and the diff lock would not disengage.

I've tried doing figure eights in reverse, driving in circles forward, cruising forward, cruising in reverse, but the locker will not disengage. I used it last weekend during another trip and it engaged and disengaged just fine. TechStream is now showing C1340 open circuit in center diff.

Any others who have had similar problems? Or have any other suggestions to try? I'm back at home now and would like to avoid driving on pavement with CDL on as much as possible considering I just had to drive it back 100 miles locked.

 

[tyl3rd]

Updating with some more troubleshooting..

Tried pulling negative terminal, didn't seem to help. I can hear the relay clicking for both CDL button depressed and released. When I release the CDL button with just acc I can hear a faint 'whirring' underneath the truck. Still haven't been able to get it to release.

 

[RedesKat]

I've had that happen, usually it's just gear wind up and driving straight in reverse, forward, reverse usually pops it out for me but seeing you've tried that, pull a drive shaft to relieve the tention? I'm not sure.

 

[tyl3rd]

I've had that happen, usually it's just gear wind up and driving straight in reverse, forward, reverse usually pops it out for me but seeing you've tried that, pull a drive shaft to relieve the tention? I'm not sure.

Are you doing anything specific in the reverse, forward, reverse process? I just made sure CDL button was in unlock position and tried several times but not sure if that’s correct

 

[TheForger]

Try doing figure-8’s in both forward and reverse

 

[tyl3rd]

Try doing figure-8’s in both forward and reverse

I did try that for about 5 minutes on grass near my house today. Should I be going longer? I’m pretty sure I just put a ton of pressure on the drive train. The locker required situation was also some tight turns :/ and being a bit of novice didn’t realize til I got back and was able to research

 

[tyl3rd]

Well, just did 20 solid minutes on a grass field of slaloms, figure eights, circles, straightlines mix of forward and reverse, no dice. Seems I've really buggered it up.

 

[MongooseGA]

That's what you get for going wheeling and not inviting us.


I kid.


Just to confirm, you're feeling the locker is still engaged, right? Not just going by the dash lights? Because the dash lights that come on the the CDL are the same that come on for my intermittent P0430 CEL.


@Wermz says light hammer taps on the transfer case.

 

[tyl3rd]

That's what you get for going wheeling and not inviting us.


I kid.


Just to confirm, you're feeling the locker is still engaged, right? Not just going by the dash lights? Because the dash lights that come on the the CDL are the same that come on for my intermittent P0430 CEL.


@Wermz says light hammer taps on the transfer case.

Yes it is definitely engaged, all the symptoms. So hammer on tcase itself and not actuator right?

 

[Wermz]

Yes it is definitely engaged, all the symptoms. So hammer on tcase itself and not actuator right?

Actuator.. the motor has probably landed in a dead spot. A few light/medium taps might help it move slightly to a better spot.. it works for fuel pumps, might work for this.

 

[tyl3rd]

Actuator.. the motor has probably landed in a dead spot. A few light/medium taps might help it move slightly to a better spot.. it works for fuel pumps, might work for this.

Appreciate the insight. Any tips for getting to the actuator? It's mounted on top of the transfer case on the 100 series. Maybe the blunt end of a chisel?

 

[tyl3rd]

And sorry, one more question, probably dumb, but if I manage to get it unstuck via tapping would I be able to hear anything audible? Or just continue trying the above steps and seeing if it unlocks?

 

[Wermz]

You wont hear anything. I messed with my actuator on my 80(same t-case) for a while before i replaced it. They never ever ever ever get used and when they do it can be trouble. Theyre a pain to reach thats for sure.. you could “spear” it with a heavy pry bar, same effect as hammer taps. Its worth a shot anyway

 

[tyl3rd]

Well, went to jabbing it with the blund end of a breaker bar (all I had with enough length) and this fell out. Screw plug and spring from the plug, spring, ball assembly by the actuator?

 

[Wermz]

That doesnt seem right… id pull that actuator off and see whats up. Look around on top of the tcase before you remove anything, you dont need parts falling inside. I dont recognize that bolt or spring, maybe look around on top with a mirror, see if you can find its home.

 

[tyl3rd]

That doesnt seem right… id pull that actuator off and see whats up. Look around on top of the tcase before you remove anything, you dont need parts falling inside. I dont recognize that bolt or spring, maybe look around on top with a mirror, see if you can find its home.

I'm ashamed to even admit this.. it's from the breaker bar and not the truck... LOL. Wow.

 

[Tanner H]

some good advice in here. my old 99 had a stubborn diff lock when i first bought it.

my trick was to turn the steering wheel full lock, put it in reverse and blip the gas pedal. you dont want to drive around in reverse, you just want to give a good quick blip on the pedal.

 

[MongooseGA]

I'm ashamed to even admit this.. it's from the breaker bar and not the truck... LOL. Wow.

Well that's better than breaking parts from the TC.

Reminds me of when I was rebuilding the hydraulic pump for my 560SEL last year. I could not figure out where in the hell this little brass point was supposed to be. Nobody could figure it out and I was convinced my hydraulic suspension would explode because of it.

Turns out it was a pen nib...

 

[hoser]

Maybe put the t-case in Neutral. Parking brake on. Wheel chocks in both directions. Then take a 9 volt battery (or 12V source) to the CDL actuator and "tap" the motor, in both directions. At least, you'll be able to verify if the actuator is moving.

 

[tyl3rd]

Thanks everyone for the suggestions.

some good advice in here. my old 99 had a stubborn diff lock when i first bought it.

my trick was to turn the steering wheel full lock, put it in reverse and blip the gas pedal. you dont want to drive around in reverse, you just want to give a good quick blip on the pedal.

best to do on a non paved surface?

Maybe put the t-case in Neutral. Parking brake on. Wheel chocks in both directions. Then take a 9 volt battery (or 12V source) to the CDL actuator and "tap" the motor, in both directions. At least, you'll be able to verify if the actuator is moving.

I'll give this a try as well, I can definitely hear the actuator motor 'whirr' after the relay clicks