Suburban 4WD problem

[skycarp1964]

I own a 1996 3/4 ton 4WD Suburban. It has the push button controls to engage the 4WD. When I push the button to go to 4HI, the light on the 4HI button just flashes forever and never goes solid like it did when the 4WD worked. 4LO does not work either.

I have changed out the two fuses that looked like they were associated with the 4WD with no effect. I am leary of taking it to a 4WD specialist for fear of being taken advantage of on the repair, so I'd like to have some idea as to what the range of problems could be. Does anyone have any insights they could share with me?

[777stickman]

I'm thinking probably the Encoder-Motor. This motor is what drives the range selection on the T-Case. The lights are flashing because the encoder-motor is not responding and giving the proper feed-back signal to say that it has gone to the selected position. In other words, the t-case is not shifting to the commanded position.

Your '96 has OBDll. If you have access to a high end scanner that can get into the 4WD system module and get some codes out of it, post them back.

Lot's of posts about the push button switch failing. I'm thinking yours is ok because of the flashing lights. But?????

[skycarp1964]

Thanks for the reply. That makes sense to me. I'll see if I can get access to the scanner.