Service 4x4 system

[HUMMERDAD]

Have seen this before and when I asked the dealer the last time they said hmmm not showing sir. So any suggestions guys
it showed up again up driving got to coffee shop shut her down come back have not seen it again. I know my trans is in need of a rebuild soon showing signs of that but nithing suvere just a little overdrive huntting. had the torque converter replaced with heavy duty unit at around 60,000 miles and got 125,000 or so now.

 

[Hunner]

I have suggested this before as it happened to me and I can repeat it to confirm. I had changed out my air filter and also was working on an intake design. I got it back together and took off for a drive. The message came up to service 4x4 system.
I checked the only things I had just done and saw that I had not fully engaged the MAF sensor plug. Pressed it in firmly and the message went away. So I unplugged it again and the message reappeared. Might be a quirk to my H3 but try removing and re-plugging that in as a wild guess.
If that is not it, let us know the solution.

oops didn't notice I was in an H2 post. yawn

 

[Big2dabank]

I have 145,000 miles on my H2 and the transmission is still holding strong, but I expect my days are numbered. I have recevie the service 4x4 light when we have been offroad the last couple of trips, but have not noticed any physical problems with the truck, only the light. Seems to come on when I really work the truck hard and the traction control comes on and off a bunch. When the service 4x4 light comes on, the rear locker will sometimes refuse to engage and just flashes at me, sometimes will engage, so its hit or miss. The service 4x4 light goes off after about 50 miles or so of normal road driving. Also when the light comes on, I notice some engine noise through my iphone adapter which interfaces through the XM recevier, kinda of like a ground loop noise. It goes away when the service 4x4 light goes off, so I suspect something electrical or dirt in a connector, etc...

Anyway it has not been enough of a problem for me yet to worry about, but its on my list of items to check out one of these days.

 

[Zach]

I have had the 4x4 service light come on before. First time was running a trail. The rear locker would not engage. After the trail the light went off only to come back on and stay on. It ended up being the coil for the locker in the rear diff. Replaced it and haven't had it come on again.

 

[Big2dabank]

I have had the 4x4 service light come on before. First time was running a trail. The rear locker would not engage. After the trail the light went off only to come back on and stay on. It ended up being the coil for the locker in the rear diff. Replaced it and haven't had it come on again.

Zach, thanks for the info, that could very likely be the problem I am having. Not suze if that helps HummerDAD any, but I was thinking it had something to do with the rear locker.

 

[Fish]

I have been getting that message randomly for the last few months, I had onstar run a diagnostic and it turned out to be my enocder motor..I havent replaced it yet but will have to soon. When I would get the message my 4 wheel mode indicator lights would show I'm in neutral when I really wasnt

 

[HUMMERDAD]

She still a mystry here but great tip haven't had any problems with my locker when mine came on we where at hiway speeds hate to see what the locker would at that .I have only had to use a few times out here no terrain nessary that I have found yet other then ditches, then yes I was very glad I had mine when I got forced off the road by a mower on a blind corner no damage just pucker factor truck was at about a 45 degree angle fully loaded with the family and our gear heading back home from VA to IL. before we moved out here.