Here is what I found on the p1850:
"P1850 Chevrolet Description
With the engine running, Transmission Control Module (TCM) High Side driver is closed, the Power-train Control Module (PCM) detects that the Band Control solenoid was commanded off and the feedback voltage was less than 2.45 volts, or the Band Control solenoid was commanded off and the feedback voltage was from 2.45 -3.53 volts, or the Band Control solenoid was commanded on and the feedback voltage was more than 4.02 volts."
I believe this code pertains to the transfer case does it seem to work okay?
Have you checked all fuses? Here is a guide to help and the fuse locations:
Check out the diagrams (below). Please let us know what you find.
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Tuesday, September 25th, 2018 AT 3:27 PM