4x4 Not Engaging

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OBXdieselAddict

New member
So after getting my last transmission put in my transfer case no longer would shift into 4x4. The lights on the push buttons did not light up and there was no sound when you clicked to change in or out of 4x4.

The switch is in good shape and would light up when we tested it, I ordered a new TCCM and replaced it Friday night. Once I did the switch lights came back on like normal and it worked.. Once, It shifted into 4L when I clicked and the lights changed and I heard the transfer case engage. What was strange was that the dash light was still light up service 4x4. I scanned for codes with my autocal and this time I actually got a code for TCCM. I got rid of the code and tried again. This time the lights still came on and you could here the TCCM click on when you cycled the key but it would not engage. Light would just flash when you clicked to change back to 2H.

Is the TCCM something that needs to be learned by the truck or something? Do I need to get the dealership to flash it so it realized it has new hardware or something?
 
It's probably the rotator splint.

[ame="http://www.youtube.com/watch?v=709nDWaYnCM"]Road Trip blind woman scene - YouTube[/ame]
 
So... thinking my transfer case is shot.

switch is good, TCCM replaced and sending signal, replaced encoder motor and it is getting power and turning.

transfer case will not engage a gear though, its acting like its in a bind and the encoder motor just tries to turn with no luck.

Should I look at getting someone to look at it or look at remans? Kinda lost at this point.
 
Can you manually shift it with the encoder motor off?

What codes are/were coming up?

Does it move in 2wd? Odd noises?

I'm sure you've triple checked already, but everything plugged in?

This all happened right after swapping out the Allison?
 
smokinVE said:
Can you manually shift it with the encoder motor off?
Didn't try that last night, thought about it but was nervous about it.

What codes are/were coming up?
AutoCal did not show any codes for the transfer case at all when I started tinkering. Once I replaced the TCCM which wasn't putting any signal out at all it threw TCCM(/AB C0323 which is why I replaced the encoder. I am still throwing the same code though as well as UNK B2585. Unrelated to this I am throwing PCM P0380 but I picked up a race valve for my rail so that should fix that. Hopefully.

Does it move in 2wd? Odd noises? Truck was blinking 4L but when I eased into the gas holding the break it turned the back tires over. It does surge and feel like its in 4L which is strange. It's like its caught between. Also no power like its in limp mode. Reverse was almost non existent. it would barely roll. When you shift to park you hear a quick gear grind like it isn't completely gripping a gear.


I'm sure you've triple checked already, but everything plugged in?
I think so, the 6 prong plug in that goes into the encoder was tight and the 2 prong wire from the encoder. There was also a small 2 prong that looked like it was coming from the transmission that also was connected into the same harness as the other 2 plugs.


This all happened right after swapping out the Allison?
Click to expand...
Yes, its been a while since I had it done but it worked perfect before my transmission was put in. The shop was a joke I went by one night and the old transmission and the transfer case were sitting in the back of the truck in the rain.. That's why I figured it could have been electrical related. Since it worked and shifted ok before then. I really don't think the tcase is locked up. Maybe its just been since it hasn't shifted in close to 2 years? About 6 months ago I changed the fluid in it just for the heck of it so its full of oil (merchant autos) tcase oil
 
C0323, is for the lock circuit in the encoder motor. Test wiring for that. If it doesn't lock it will allow the t-case to "jump" out of gear.

B2585, did you plug your head light switch back in when replacing the TCCM?

p0380 is a glow plug code....
 
smokinVE said:
C0323, is for the lock circuit in the encoder motor. Test wiring for that. If it doesn't lock it will allow the t-case to "jump" out of gear. Real dumb question... Whats the best way to test the wiring? test light into each of the positive leads? Which ones should be running current? I might have to find a more electrically inclined buddy to check out the wiring harness lol

B2585, did you plug your head light switch back in when replacing the TCCM?
I don't think I had it unplugged it may have come loose I'll pull the dash and check it out.

Thank's for all the trouble shooting help. Hugely appreciated!

p0380 is a glow plug code....
Click to expand...

Alright cool I thought so, That will be a tinkering session for another day lol
 
Test light, not LED or DMM! Check for power on the Orange wire (cavity M) at the body side harness for encoder motor. Using the tan wire (cavity E) as your ground. If it lights up the circuit tests good.

NOTE, may need to clear the code for the TCCM to to ground the circuit. Should always have power as the ATC fuse feeds directly to the encoder motor.

Using a DMM on the encoder motor test for 18-25 ohm's of resistance Orange cavity C, tan cavity D, if more or less internal encoder motor failure.

Savvy?

If all good report back and we'll dig further.
 
smokinVE said:
Test light, not LED or DMM! Check for power on the Orange wire (cavity M) at the body side harness for encoder motor. Using the tan wire (cavity E) as your ground. If it lights up the circuit tests good.

NOTE, may need to clear the code for the TCCM to to ground the circuit. Should always have power as the ATC fuse feeds directly to the encoder motor.

Using a DMM on the encoder motor test for 18-25 ohm's of resistance Orange cavity C, tan cavity D, if more or less internal encoder motor failure.

Savvy?

If all good report back and we'll dig further.
Click to expand...

Sounds good! it'll probably be Monday or Tuesday. Thanks again for the help.

Butt hurt I wont be able to race tomorrow. The Street Outlaws TV show will be in Fayetteville NC tomorrow and its open to diesels. Couple buddies will be beating on some gassers though so it should be a lot of fun.
 
smokinVE said:
Test light, not LED or DMM! Check for power on the Orange wire (cavity M) at the body side harness for encoder motor. Using the tan wire (cavity E) as your ground. If it lights up the circuit tests good.

NOTE, may need to clear the code for the TCCM to to ground the circuit. Should always have power as the ATC fuse feeds directly to the encoder motor.

Using a DMM on the encoder motor test for 18-25 ohm's of resistance Orange cavity C, tan cavity D, if more or less internal encoder motor failure.

Savvy?

If all good report back and we'll dig further.
Click to expand...

Sorry it took so long to get back to you. Been a crazy week at work.

So I finally gave up and had my buddy take it to an electrical mechanic with his tow truck. Long story short my encoder motor was my original problem and when I replaced my TCCM the one I replaced it with (reman) it was bad so I created a second problem after putting that in. They threw my original TCCM back into the truck and its working perfect now.

So now that I finally have 4x4 locking right again we are going to start tearing into her Friday to start installing the TCT S475 :charger: So excited, Id like to throw a 10mm pump on at the same time to help feed the 65 overs but I'm worried about my stock bottom not being happy for long with a good pump. Might wait a bit on doing a pump until I'm closer to being able to afford a bottom end build.

Thanks so much for all the help its greatly appreciated!!

Vince
 
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