Heater and instrument panel

[snoykster]

Noob, here and I am looking for an answer as the cold is here and I am having issues with a 2006 trailblazer.

My sister and her husband have had this TB for a couple of years now and issues have arisen starting last year. It seems that the cold brings it out of this vehicle as it works the rest of the year but once it gets cold, it starts acting up. The heater blower stops working, instrument panel lights all come on and stay on, and (if I remember from last year) the 2wd/4wd will not engage. They took it in to the shop last year and had it fixed. By what my sister said, it was a simple fix and probably could have been done by me. (Her husband is mechanically inclined)

A year goes by and everything works just fine, now the cold is back and the problem is back (not sure about the 2wd/4wd but everything else). I would do the "simple fix" if I knew what it was. Sister lost the paper work from last year so I have nothing to go off of. I checked the fuses and relays in the fuse box. Everything checked out.

I did a quick search on here for things but all I could find is relating to the relay resistor for the motor. If it was just the blower, I would do that but it seems to be the whole package again.

Any suggestions or ideas of this could be? I will keep asking for my sister to find the paper work but I doubt she will find it.

[maxwedge]

Welcome to AF, vague question at best, many things can cause this, check for power in and out of the ign switch for these circuits, or contact the shop and see if they have records of the repair. We need to know exactly what works and what does not.