Problem Description and Possible Solution
The 4WD transfer case encoder motor position sensor or the selector switch may fail causing the service 4WD message to be displayed. Fault code(s) stored in the transfer case control module will be of assistance in determining the exact fault causing the message to be displayed.
Average mileage: 123,568 (50,900–237,000)
Drive Trains affected: 4WD, 5 Speed Transmission, 4WD, 6 Speed Transmission
24 people reported this problem
Hey all. This morning like most mornings I used my automatic start to start my truck to warm her up (08 GMC Sierra 2500HD 6.6L SLT Z71). After letting her warm up I got out to get in and its roughly around 32 degrees. I get in and go to put her in drive and get a "Service 4 Wheel Drive" message in my DIC. I have never had this message pop up before. I tried turning her off then turning her back on, same message. Then it says put in N to reset, I tried that and nothing happened. The indicator light on the 4 wheel driv not illuminated as usual and the truck won't go into gear and drive at all. I checked the 4 wheel drive system fuse and it seem to be ok. Any Ideas??? And help would be much appreciated
4 by 4 switch will not engage, when truck is started n appears on switch then shuts off, display says service 4 wheel drive, when put into gear a rough jerking motion starts and truck seems to not want to shift up and in reverse truck will suddenly come to a lock stop and not want to back up anymore
I have determind that you need to relearn your transfer case encoder motor. This can be harder then you think. First make sure your battery has plenty of power. I hook up a battery charger and then i use a good diagnostic computer. before you can do anything else depress emergency brake, transmission is in neutral, key on. Clear the code c0569, at this point you can relearn the encoder motor. If encoder motor won't relearn then back out of computer reverse procedure, disconnect the battery, reconnect battery and repeat if needed. It will eventually work. I hope i have helped some poor suol out there that made the same mistake i did in buying a computer controlled truck. GOOD LUCK
2004 silvarado crew cab, 100000 miles, service 4 wheel drive message, code c0306, stuck in 4hi, cleaned ground on body mount no change.
I started my 2013 GMC Denali Duramax HD Allison Transmission 2500 truck and attempted to pull out of a parking spot. I immediately noticed the truck was not operating correctly and got warning lights to service the Stabilitrac system, the 4 WD system, & the Traction Control. I called my dealer who suggested that the truck was stuck in 4 WD low, and told me to go ahead and drive the truck to their shop. I couldn't drive over 40 mph. The dealer said they could find no fault codes, they recalibrated the shift positions, and declared the truck fixed. Since they didn't replace any parts, they claim that my warranty will not cover the repair (besides the manufacture warranty, I had purchased a 7 year 120,000 mile extended warranty). They have yet to explain how the truck put itself into 4WD low in the first place.