2016 Yukon XL in stuck in 4WD hi. Some of the codes I've pulled are U0403 Anti Lock Brake System, P0652 Sensor Ref Voltage B Circuit Low, C0398 Range Actuator Pos Correlation. I know sometimes it can be one thing that throws all these codes and I've checked the #6 fuse. Any one know where to start in searching for what I need to do to get this back into 2WD? Thanks and God bless!
codes I've pulled are U0403 Anti Lock Brake System
That might be the module it came from, but code actually means
U0403 is "Invalid Data Received From Transfer Case Control Module"
Basically all your codes are related to the transfer case module.
Always read the bulletins for your vehicle :
https://static.nhtsa.gov/odi/tsbs/2017/MC-10130547-9999.pdf
https://static.nhtsa.gov/odi/tsbs/2019/MC-10160646-9999.pdf
You can get them from https://www.nhtsa.gov/vehicle/tsbs
@imperator Thank you very much for your comments. Thank you also for the bulletins you've sent. I'm be sure to follow those as a reference in the future. Lastly, I finally tried something last night and unplugged the negative terminal of the battery for 35 minutes and it ended up resetting the system. I had disconnected the battery in the past but only for 10 minutes or so. Nevertheless, another blog I read recommended doing that for 30min to an hour. Nevertheless, I'm golden as it's now switched back to 2wd and my wife can drive it again!
I would check the wiring on the TCCM itself for damage. It could happen again and leave your wife stranded.
unplugged the negative terminal of the battery for 35 minutes and it ended up resetting the systemUnless the negative battery terminal was loose or something I would be skeptical of the issue being 'fixed'.
