TrailBlazer/Envoy 4WD Front Axle Disconnect and Actuator Operations Demonstration.

[@Ed-dr6qc]

Great video series on the Trailblazer front axle and actuator operations. I watch them all and learnt alot. Thanks Tom!

[@thomasjbaker7688]

I only started putting these videos here to document my experiments for my own purposes. I forget a lot after I have done something !!

[@Pluto-fu3fq]

What’s up, i’m the guy on GMT Nation, BenjaminBlazer. Would i be able to hear the noise even while still plugged into/screwed into the disconnect?

[@thomasjbaker7688]

Yes, the sound is loud enough to be heard from the drivers seat even. That is as long as the engine isn't running and the radio isn't cranked up!

[@Ed-dr6qc]

Tom which activate first when you turn the 2wd to 4wd selector switch. The transfer case motor or actuator. I am stuck in AWD and when I turn selector switch I don't heard anything. Is motor or actuator bad? Thanks.

[@thomasjbaker7688]

The two are nearly simultaneous. The switch from 2 Hi to A4WD or 4 Hi takes about the same time for both the front acle disconnect and the encoder/shift motor.

[@thomasjbaker7688]

If the service 4WD light is on in the instrument panel cluster you can try resetting the control module by removing the #8 ATC fuse in the underhood fuseblock for a minute or so then reinserting it. There is a second fuse for the 4WD in the rear fuseblock under the back seat but that one does not reset anything. That said, if either fuse is bad the system will not work for 4 wheel drive.

[@Ed-dr6qc]

@@thomasjbaker7688 Hi Tom: The fuses are all good. There is no warning 4wd light on dash. When I move selector from where it is stuck now, AWD, to 2WD all I get is a click and it then default to 4WD hi. If I switch from 4wd hi to AWD it stays there after its blinking sequence. I just cannot get it to 2wd.

[@thomasjbaker7688]

​@@Ed-dr6qc I cannot think of anything that should make a click sound. There are no relays involved. Where does this click sound come from? If the light is on at Auto, and you mive the switch to 2 Hi, the light flashes at 4 Hi?? If yes then I think the switch may be the cause. Some people say to turn the switch back and forth to all positions in an attempt to 'clean' the contacts inside the switch. Key OFF of course.