First thanks to all of you here on the forum. This is my 1st post... Here is my problem. I have a 95 push button 3 button switch 2hi 4hi and 4lo the problem is weird as the truck will go into 4lo if I go to neutral and en engage it other times I hear clicking when I hit the 4lo button but both lights on the switch stay on. The 4 hi option would not work at all until I did the battery disconnect method only problem with that is after The truck sat for a little bit back in 2hi it will no longer engage 4hi so back to square 1 for me. I can tell you for sure that it did in fact go into 4hi just not anymore. I am going to do battery reset again I have a felling it will engage again but will only last for a very short period of time. All help will be greatly appreciated. I just got the truck 3 days ago incase you want to know history. Thanks again,

Mike

*Combining Consecutive Posts*

Disconnected battery really quick and tried 4 wheel drive hi and worked like a charm. Anyone have any ideas of possible problems.:icon_bike: Ok back to problem 1. 4 wheel drive worked ok several times and then back to 2 hi this time I have a tccm stored trouble code 2 ?? Anyone ???

Code 2 is an encoder fault. The battery disconnect will likely only be a temporary fix until the TCCM gets another encoder fault. Check the Tech Article (DIY) section for further information on transfer case diagnosis. Either the post by error_401 or by lastcoupe.

what causes a encoder fault? This sounds like my same problem. The tcm was bad so i replaced it and now this is pretty much what its doing? Can you do something wrong when putting it in to give it a fault? Ive tried the fuse removal any nothing helps. I just dont want to put another one in and it d the same thing.

The encoder itself is a position sensor that is attached to the shifter drive inside the encoder motor on the transfer case. It is comprised of 4 traces each having varying degrees of rotation for a given contact path. The TCCM monitors the channels (the contacts inside) as it rotates the encoder motor. If the channels drop out unexpectedly during a shift, the TCCM will throw an encoder fault and attempt to return to the previously selected mode.

As far as what causes encoder faults... Could be anything from an intermittent connection at the TCCM or the encoder motor wiring connections to a physical problem with the encoder itself.

If you have only been replacing the TCCM inside the truck, you have not dealt with the encoder at all.