4 wd will not engage

BassSJ · June 22, 2004

I have a 99 1/2 ton 4wd, old body style with the electronic transfer case. Last night I noticed that none of the indicator lights on the dash for 2 hi, 4 hi, or 4 lo were not illuminated. I started pushing the buttons and nothing happened. I could never get the 4 w d to engage, the light never came on and the rear wheels were still slipping only. Any body had this same problem. I hope it is a simple switch or something. I really like the floor shifter a lot better, nothing like hearing that "keeerthunk" when you grab that shifter.

Jeremy WI · June 22, 2004

I am not sure about the 99 models, but my 96 uses 3 fuses for 4x4, gages, 4wd, and transfer case. The gages fuse sends the power to the push button and the 4wd is for the front axle actuator, and transfer case is for transfer case motor

nhproxr · June 23, 2004

I just had a problem with the switch in my '98 Yukon. I'd be driving along and the lights would go out. With mine though I could still engage 4wd, then in a few miles that light would go out too. Turned out to be the switch, just swapped it out tonight. Might want to try a new one first, cost $42. If doesn't work, might be encoder motor in t-case. Very costly. I guess sometimes this motor goes out of sync and can be reset by pulling the fuse, cycling the key then putting fuse back in.

BassSJ · June 23, 2004

I checked the fuses last night and they are ok. When I first turned the ignition switch on, the 2 wd light did not come on. I checked all the fuses with a test light and they all were ok. I then turned the ignition off and then back on. Instantly the 2 wd light came on. I fooled with it for a couple of seconds and the 4 wd high and 4 wd low both engaged. I think I might have a in dash switch in the process of going bad. I will keep an eye on it a lot closer now and replace that if it acts up again. Thanks for the help. I really appreciate it.

nhproxr · June 24, 2004

Yeah if I pushed on mine a little bit it would make the light come back on for a little bit, sounds like the switch that's good news compared to how expensive it could be.