Help! I tried switching the transfer case **** to 4 HI on my 2002 Trail Blazer and nothing happened. The light went off on the 2 HI setting and won't come on again. I tried driving up and down the road and turning the ****. There was no change. The light won't come on in any setting .It's not making any grinding noises or anything so I'm wondering if there is a wiriing or fuse problem preventing the transfer case from getting the message? Does it sound like a flukey minor problem or a big expense problem? I'm a single mom with no automotive capabilities! It's no longer under warranty so I'm trying to do a little research before I take it to a dealer. Thanks!

 

I know on most 4x4 vehicles there is a 4x4 engage sensor that can go bad in the transfer case. They're not that expensive, if that's your problem. Does it feel like it is actually engaged in 4wheel drive or just 2wheel drive? If it is in 4x4 you should feel the front wheels pulling the car (a little) in whatever direction you'returing when accelerating.

 

Other than the 4x4 light not working arethere any other issues with the operation of the trailblazer???

If so then it could be related to that. But there is an issue with the TCCM (Transfer Case shift Control Module) it is located under the dash...if it sets a DTC in the modules memory then it will only shift between 2hi and 4lo until the problem is fixed....there is also a vacuum switch that controls the differential engagement but if you have AUTO 4x4 then i don't think that you have that engagement issue...

 

i am having the same problem. I live in denver and it is the peak snow season so i am trying to fix the problem soon. did you ever find out what the problems was or is?

 

It's that the transfer case module goes into a sleep mode. Pull the ATCM fuse for 2 min and check to see if that works. GM states that if it does you need to replace the ATCM module mine did it 2 years ago and is still working fine