MBman

First off, great site. I am an old car guy and these sites really help me out , I don't really understand all the new fangled electronics. So here is the problem, on my wifes 2003 suburban 4wd, 1500 the service 4 wd light has come on in the little view area where the odometer shows. the lights on the side where you can select 4wd,2wd ect are no longer lit.
What can be the issue? and is it safe to drive, dealer only fix?
Thanks in advance

ZX1100F1

I would wager a bet that the Transfer Case Control Module (TCCM) needs to simply be reprogrmmed with updated calibration software by the dealer.
Have the dealer reference GM Document # 1341278.

If you can go to an auto parts store and have them retrieve the DTC (diagnostic trouble code) I can help you in greater detail.

vf171

One other thing to check, the Airtek switches in the newer chevy's are junk. I've had twoof them go bad, the solder joints break. You can either pull the switch and de-solder it then resolder the contacts or buy a new one (~$64). I think Rock Auto has them.

I don't know about the software update though. That may be a known problem as well, probably is considering GM has a document covering it.

Have you noticed that the light comes on whenever you are on rough surfaces or the rig gets jostled around somehow? Anytime I'm on gravel roads or one with a lot of pot holes the light comes on. If you have similar symptoms check into the switch.

Goodluck.

EDIT: I forgot to add, it should be safe to drive if it's the switch. Also, my indicator lights go out on the switch also when this happens.

MBman

Well the light is off now, I got under there and pulled the tranfer case plug, cleaned it out and now the light is out, not sure what I did actually helped or if I had some kinda electrical hiccup. In any respect I am going to go and see if it set a code, thanks for your input

Velonika Tahiti Tiumalu

my 2003 z1 tahoe service 4wd display and not sure why da wheels are trying to lock when I tried to turn or drive it....what should I do or what really needs to be done. Please I need some info

73shark

Welcome to the forum.

You might try selecting four wheel drive and two wheel drive to see if they will engage properly.

SWHouston

This is a comment on 4WD in general, I'm not pointing my finger at the OP or anyone else posting, but...

90% of the problems I read are caused by non-use.
People buy 4WD most times because it's "cool" to have, then, totally forget that they have it under there, and never engage it in hi or low, or, change the Fluid for that matter.

The situation is, "Use it or Loose it" !

Cases get "gooped" up from non use, and when someone tries to engage it, it just doesn't transfer, and frequently takes many attempts to transfer, before you can get a single change out of it. AND, when they do get it to change, think all's good now, but they're wrong again.

You MUST do regular maintenance on a Transfer Case, weather you use it or not.
(change Fluid every 25-30K mi)

You should (if you're smart) put it in 4WD-hi frequently, every week or so.
(just for a few minutes, then back to normal)

You should put it in 4WD-lo at least once a Month, and drive it at least a Mile.

The reliability is not so much from the use (time/distance) it's self, but, from making it change on a relatively regular basis.


Proper Fluid for these Cases is AutoTrak II, about 2 Qts.

73shark

I agree w/ all of the above but I'd have a hard time finding a place to drive in 4WD LO for a mile.

FWIW: my wife's new Sequoia's owner's manual states that you should drive ten miles a month in 4WD.

SWHouston

I live sorta buried back in a residential area, and the speed limits are 30mph. So, it's not hard to exercise the 4WD for me. I run in the mid/upper 2000 rpms to keep up with street traffic.


Also, I do it on a no rush trip, grocery, fuel, something where it's not necessary to hurry. I am continuingly impressed, as to how much power our rides have in Lo Range.