So as I was driving to work today I see that the lights on the selector switch all lit up and then went out. This happened three times. I have not checked the connection to the transfer case yet but will do so today. Just thought that the new developments might shed some light.

 

I need to replace my TCCM, as well. How do you release the electrical connectors? Do they have only the one lock tab (that can be seen) on the bottom side of the connector, or is there also a hidden one on the top side of the connector that needs to be squeezed? Thanks!

 

It's been awhile but I think think the release tab is only on one side. Most are. The conventional technique for removing sticky connectors is to oscillate the connector in the X and Y axis with 2 Newtons of tab pressure. The connector should release in the direction that propels the back of your hand into the sharpest object under the dash.

On a more serious note (not related to your post, Skyward): We're all happy and desperate for help when we consult the forum and are glad for the help the forum provides. When your crisis is resolved PLEASE take the time to post your results so others can learn from your experience. I'll also take this opportunity to thank Hydrashocker & Sharpstr325 for all their time, expertise, and patience helping the brother&sisterhood. Enuf said.

 

You were precisely correct, even to the hand propelling into the sharpest object!!

Further questions...Is it necessary to disconnect the battery negative cable when installing the replacement TCCM? Does the TCCM come 'online' without any programming?

Thanks!

 

yes you should disconnect the battery whenever you do any electrical work

 

Okay, I found a TCCM from a junkyard http://www.uneedapart.com/ ($40.00 including shipping) and installed it. My 2WD/4WD switch lights up and works as advertised!

I might point out that no one could offer me any compelling reason to disconnect the battery and I did not see it necessary to disconnect it for this, so I didn't.

Thanks, everyone, for your inputs and assistance!

 

the reasoning behind it is simple, whenever you are doing electrical work you run the risk of sparking and shorts, if you have a short or a surge (sparking is indicitive of a surge) you run a very high chance of damaging one of your electronic modules (usually the one you are working on)

 

I was looking for a reason why my dash is showing "Service 4wd" The 4Wd is working fine, but this light is always on. Was told that this could be the TCCM but my understanding is that if this module is broken, it will not shift the drive from 2Wd to 4Wd.
Is this correct? If so, is there another module that could cause this failure indication?

 

Most likely it is the module, but get under it and pull the harness off the T-case. Look for corrosion and unplug and plug in a few times to make sure it is getting a good connection.

 

Thank you hydrashocker. I will do that and keep you posted.