How is everyone doing? I am new to this forum but I belong to preunner.net. I also own a 00' S-10 I am turning into a prerunner. OK here we go. I bought my wife a brand new 1999 ZR2 Blazer. It sees very litle off roading except for the beaches of Denmark (bought in Germany). It just hit 84,000 miles I keep it well maintained. When I push the 4HI and or 4LO buttons, they blink and I hear a "clicking" sound from what I can tell, under and behind the glove box. I took it to my local Chevy Dealer and they said that 90% it is the switch. Well I bought a new switch and I guess that I am part of the 10% because it still doesn't work. Please brother I need some help on this. This sight looks awesome, glad I joined

 

I would say double check your wiring. and if that isn't the case the next thing I would try is putting it in 4Hi or even 4 Lo while being in neutral. and see if that works. i've had it do it to me a few times but It hasn't done it in a while on me.

 

ceanern,
What wiring are you talking about? The wiring in the switch? When I replaced it with the new one, they are "snap in" connectors and they appeared to look alright. I will recheck them. Was also going to open up under my glovebox and see if I could tell where the "clicking" sound is coming from. I will also try the neutral selection. Hey brother I am open to anything. I've got to get it operational. Thank you

 

Was meaning to double check the connections. was hoping for more ppl to chim in on it. sounds like it wants to engage, Just isn't engaging. Is it just clicking a few times when you push the button and not going in? Wondering if it isn't possibly the actuator(sp) that controls the engaging mechanism

 

Ya it only clicks once on every push. When i pulled the connections off the old switch, they were really tight.

 

You blew your transfer case fuse, its a 20A mini. The real cause of this problem is the push buttons themselves. Get a new one at the dealership, 25 bucs for a brand new one.

 

HillbillyinOhio,
OK I will check my fuses tomorrow. I am in Cali right now (it's 2030) and I am in the Army and wake-up is 0430 so I will check tomorrow after work. What are you saying costs $25, a new switch (4x4 buttons?) ? If so, I just bought one and put it in and still "nothing" but a "click". So somebody help this soldier please. Thanks Brothers

 

There is an actuator motor called the Encoder motor on the transfer case that might be the problem. If you are on base then see if they have a mechanics section where you can use a scan tool and find out what the path to the problem is. When all else fails take it back to the dealer and have them test the Transfer Case Shift Control Module, it determines if the conditions are correct to shift the transfer case, if this module is defective then the Encoder can not shift the transfer case to your button selections.

Have you tried to shift into 4hi/4lo while in neutral?

When each of the switches is depressed they will complete a circuit through their own specific resistor. The transfer case shift control module continuously monitors the switch input to determine whether the 4HI, AUTO 4WD, 2HI, and 4LO button selections are made by the driver. Neutral may be obtained if the following conditions are met:

[ul][*] The engine is running. [*]The automatic transmission is in neutral (or the clutch pedal is depressed on a manual transmission application). [*]The vehicle speed is below 3 MPH. [*]The transfer case is in the 2HI mode.
[/ul]
Once these conditions have been met, pressing and holding both the 2HI and 4LO buttons for 10 seconds will shift the transfer case into neutral, turning on the red neutral indicator lamp.

 

My money is on the fuse being blown

 

I had the same problem. Take out your battery, then remove your battery tray. You'll see the device that engages your 4 wheel drive. (I can't think of what it's called off the top of my head.) Anyway, there is a rubber bladder surrounding it that creates a vacuum when you push your 4 wheel drive button. It pulls a cable when activated and engages your transfer case. If the bladder is cracked or dry rotted, you'll lose vacuum and your 4 wheel drive won't engage. I would check that. It's a common problem. By the way, it's a dealer only part and costs around $85. If that's the problem, it only takes about 30 minutes to do the whole job.