stuck in 4 wheel on 1999 GMC Yukon Denali

it is stuck in 4 wheel high, how do i diagnos this problem?

by in Pewaukee, WI on April 26, 2009
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6 answers
ANSWER by , March 28, 2010
put the truck on neutral and change to the desired setting
ANSWER by , September 09, 2010
i have the same truck with the same problem. the plug on the drivers side of the transmission over crossmember came loose and some pins were green from water getting in there. if thats your problem get some small brushes and take your time cleaning them. dont bend any pins spray with contack cleaner and blow dry. it worked for me
ANSWER by , May 01, 2009
The 4WD system is controlled by a computer. The computer will store fault codes when it detects a problem with the 4WD system. You will need to access the fault code(s). The stored codes should point in the direction of your problem.
ANSWER by , July 02, 2009
Had the same issue while in the OBX. Ended up being the last thing I checked working from the top down. Check the plug connection on the tranfer case. Mine came unplugged and the transfer case was not getting the signal from the computer to change. No fault codes were stored.
ANSWER by , December 19, 2010
stuck in low 4wheel drive
ANSWER by , April 21, 2011
Denali's are ALL WHEEL DRIVE. All 4 wheels pull all the time