4x4 has been working perfectly since that last instance mentioned... I've been using it in the snow, offroading, offloading in the snow... It has been working very well, truck will go anywhere!
until Sunday... I was driving back to school and it worked when I left my parents to get me up a hill in the snow by their house. All highway driving for an hour or so then I needed it when I got on back roads. Tried to engage and the light just kept flashing. Ended up fishtailing excessively the rest of the way to school in a few inches of snow. I doubt I'd have made it without weight in the bed. I tried several times to get it to engage: forwards, reverse, neutral, and various speeds. I got nothing but flashing lights. Now, the next morning I drove it to the grocery store and it engaged perfectly.
I think something (possibly the tccm) might be overheating. I've only had these issues after the vehicle has been running a while. At the same time, A month ago I drove it three hours and it still worked at that point so I'm not sure, then again it was below zero F that day. It's very sporadic and random, but it may leave me stranded some day...
2005 GMC Canyon SLE z71
3.5 inch zone combo lift
33x10.50r15 BfGoodrich All-Terrain T/A KO
Supermodulation Performance Package and Tune
Kennwood head unit and speakers