4wd Indicator Light And Transfer Case Behavior

[mashephe]

Hi all,

 

I've got a 98 K1500 Silverado with 4wd. I just purchased this and want to be sure the 4wd is operating as it should. It has an electronic transfer case, with push-button 4wd controls below and to the left of the climate control. The indicator lights on this electronic control don't seem to behave as the owner's manual implies they should. Here are some of the symptoms:

 

First, when the truck is running and shifted (presumably) into 2Hi, none of the indicator lights are on. Is this normal or should the 2Hi indicator be lit?

 

The owner's manual seems to imply I can shift from 2Hi into 4Hi in any gear at any speed by touching the 4Hi button. When driving down the road at 30 mph and I push 4Hi button nothing happens. No noise, no blinking... nothing. Is this normal?

 

If I am in neutral and the truck is stationary I can shift into 4Hi or 4Lo. However when the truck goes into 4Hi or 4Lo all three indicator lights flash and then all three remain lit (2Hi, 4Hi, and 4Lo). I get the same behavior whether shifting into 4Hi or 4Lo. However driving the truck seems to suggest pushing the 4Lo button really does put the truck into 4Lo (it is geared way down). It is a little harder to tell if 4Hi is engaging, but I hear some clunking sounds that make me think 4Hi also works. I'm just puzzled why the current state is not reflected in the lights by having either the 4Hi or the 4Lo light lit.

 

Every now and then when I am in neutral, stopped, and try to shift from 2Hi to 4Lo or 4Hi the shift fails. All of the lights will blink and then all go back off.

 

Are these symptoms indicators of a common problem? If so is it likely to be a problem with the switches or the components at the transfer case? Any help in trouble-shooting would be appreciated!

 

Thanks!