service 4wd

[gribby]

Yesterday I had a very strange experience, and am looking for help. I was in a parking lot approx 10 min after driving to the store. Returned to my 2000 Envoy to return to work. I turned it on, put in D, and felt nothing, no gear change. I tried the gas, it was like I was in neutral or park... no movement. Tried all the other gears, and no movement.

I noticed the Service 4wd idiot light was reminding me that I'm an idiot. First time this has lit up.

Mechanic has determined that there isn't an issue with the tranny. Any body ever experience this...is it a transfer case issue, or a switch that has gone into some safe mode?

There was an issue a couple of weeks ago, where I could not get out of 4LO (in a snow covered driveway with an up hill exit). Once I turned off the vehicle for a couple of minutes I was able to restart and get it back to 2HI.


ANY HELP WOULD BE GREAT.

 

[Molson02536]

Check the 4x4 electric motor actuator on the transfer case. You should hear it work from 2wd, 4hi to 4low and back to 2wd with the push of the switch. If you don't hear it working then check the wire harness at the actuator motor, look for any damages like corrosion or cracked wire connector clips. If you have the Automatic 4WD button, there more common to have problems due to the extra speed sensor and wire leads. There is a speed sensor on the front prop shaft housing and rear drive shaft housing which determine when the 4wd should be activated when the front and rear drive shaft differ in speed. As you mentioned , you may have a bad wire harness to the transfer case actuator or a bad actuator it self that has a short in it. The wire harness is on the drivers side and may be loose causing a short making your transfer case not shift properly or shift on it's own. Good luck and keep me posted, be glad to help you get your jimmy running 100% again soon. In the mean time if you don't need your 4wd, pull the fuse to your 4wd at the fuse box at the end of the dash drivers side, this will keep your transfer case from shifting on it's own till you get it serviced or inspected for safe use.