2006 chevy 2500 lbz duramax

I was driving in some snowy conditions a while back and all of a sudden the brake light antilock and service 4wd popped on and at the same time the blower motor quit working. I figured the lights were cause by a iced up wheel speed sensor so I thawed the truck but had no luck. I checked all of the fuses then removed the grounds and cleaned them. Replaced the batterys making sure the cables were clean and tight. I tested to see that the blower motor worked and it did. Also I replaced the resistor for the blower motor and the climate control switch. I also noticed the pigtail to the blower motor had been replaced and looked to be in good condition. I then back probed the pigtail on the blower motor from 12v power to the high fan setting. When jumping power at the pigtail the fan turned on and dash lights went off but as soon at you unhook that the lights come back on

 

My 07 is doing the same thing mine is a 1500 2wd though I just bypassed the resistor with a toggle switch but yes my abs light is on still gonna try to scan it tomorrow at work

 

When i bypassed the resistor to the high setting it would put out the abs, brake light and service 4wd. I was hoping to get it hooked up to a better scanner to see if there codes stored. Did you have any luck diagnosing this issue.

 

The codes were
u1000 class 2 data link malfunction
c0379 front axel control circuit malfunction
b0790 transfercase neutral indicator malfunction
p0504 brake switch circuit 1-2 correlation
u1041 lost Communication with electronic brake control module
p0621 generator L terminal circuit

I feel like these codes are connected to the same malfunction because all of the lights came one and the blower motor quit at the same time and everything worked as it should before. Any information would be greatly appreciated.

 

Try turning the key back a hare after turning on the vehicle I had the same problem. Ignition lock cylinder.

 

Resolved the issue by replacing the ignition switch behind the lock cylinder. Also replaced the resistor to be safe.

 

I have the same issues Schmidty and will try the ignition switch. Appreciate you updating this thread with your solution