Hey everyone. can anyone give me some advise. My 03 Hummer H2 has 67K on it and the vehicle has never been off-roaded by the prior owner now me. For the past 4 months I've been getting this "Service 4WD" message on the DIC. I've read that GMC has had issues with this occurring when 4wd is rarely used. I replaced the TCCM and the actuator but it still persists. I have heard that the wiring harness for the transfer case become corroded and cause this message to appear. What a surprise, take it to the Chevy dealership in Punta Gorda Florida and they say I need a whole new transfer case. That's just a bunch of bull. These trucks are beasts and you mean to tell me that a truck with only 67K, in mint condition needs a new transfer case, I'm suspect. Has this ever happened to anyone and could help me out on this. My e-mail is kevinbetts@phhf.com Any help would be greatly appreciated

 

Welcome.


Your post was MOVED to the H2 section. What would be the point of asking a question about your H2 at the end of an OLD H3 thread. If you have an H2 question.............. it goes in the......................H2 section.


If I was you I would delete your email from your post, otherwise it will be packed with spam from all kinds of lowlifes from here on out. If people chose to contact you directly, they would do it through a Private Message.

 

Try to check older threads about the same subject. Don't rush to change your transfer case especially when dealership told you to do like that! Try this:
When your truck in static position( not moving), try to press 4HI LOCK button and after press 4HI button back. You should do it at least 20-30 times switching your TC modes back and forth. In this case your TC motor became activated and engaged in changing TC modes when you pressing those buttons on your Hummer's front panel. When you don't use for a long time your 4WD system this kind of Message"Service 4 WD"could happened! I had before several time this kind of Message and one good mechanic fix it for me and told me how to do this procedure if message will go back in future. Try it before you start to change different part for your TC. After this procedure your message should be disappeared.

 

I had a wire broken to the transfer case. Sometimes the tranny would act weird too. 4wd came on too. They fixed the wire and it fixed it all. Tranny back to normal too

 

The button packs have also been the culprit for many members. Replacing the 4x4 switches may fix it. Mine used to give me that error on a pretty regular basis then it just went away. Hasn't happened in quite a long time *knock on wood*

 

Did you get this fixed? If not, do you have lights on the buttons? If not check for power from the fuse block. I had a mouse eat a bunch of wires on my '03.

 

Obviously you need a new transfer case, brakes and new tires! Haha...these dealers are awesome!

 

I agree, run through the buttons, several times, that should solve your problem...what have you got to lose

 

Someone told that the H2 should be run through the 4x4 buttons on a regular basis e.g. once a month as this warning is programmed to come on.

Not sure I believe the last part but other threads tend to support the regular bit