I’ve taken my hummer to 2 different dealers and they don’t know what’s wrong with it. They thought it was the differential or the new aftermarket radio or macho. They change the macho but it still doing the same thing. They had me buy a differential but that wasn’t it either. A lot of these dealers really haven’t worked with Hummers. The hummer drives fine as long as you’re going straight. But once you turn right or left it seems like it’s on 4 x 4 the wheels get a stuck a lot. It killed my new battery three times. Sometimes the radio, windows, AC and needles on the dashboard won’t work and then all the sudden they work again. The switches for the 4x4. only the top one switches to 4x4 which is the H2 and Second and third ones Won’t switch. PLEASE HELP E-mail babbyf1@gmail.com

 

MOVED. All H2 questions go in the H2 section, not the H3 area. Miles and symptoms would be important when asking for help.

Welcome to HF and good luck.

 

Need a little more history:

• was your truck running OK before the aftermarket radio was fitted?
• did this fault just suddenly occur?
• has any work been done recently?
• have there been any water leaks?
• any damage?
• are there any warning lights?

There are so many possibilities here:-

• possibly a bad or lose ground connection which is affecting serial comms.
• water ingress causing the same thing (check for leaks, cable/connector damage etc)
• some aftermarket item is killing the comms and/or draining the battery (good place to start)
• excessive current drain (dead battery) need sorting. Check anything plugged-in. Onstar is another possibility.

The issue seems connected to the "Transfer Case Shift Control Module" (located behind the headlight switch) but that's just a guess on my part. I see there is a body ground connection to it located under the left rear door. There is also the "TREC" Fuse near the battery could be corroded/intermittent. Sounds like your diff is stuck or being actuated when it shouldnt be, could be a faulty TCSC Module?

If possible find someone with a TECH2 to help you.

And being a Brit, what is a "macho"

 

And being an American, what is a "macho"

 

Does my H2 have a Macho? If so, where is it located?

 

Letty Phyllis take a look at this thread regarding splice packs

 

Apologies missed the actual link here