1999 Chevy 4X4

Discussion in '4X4 Truck Talk and Repairs' started by texasaggie23, Dec 14, 2009.

  1. texasaggie23

    texasaggie23 New Member

    Messages:
    35
    State:
    Texas
    Have a quick question for anyone out there.

    -I have a little problem with my brother's 99 chevy z71. It is the 90s body style and has the 4X4 switch on the dash. When we tryed to put it in 4X4, the transfer case wouldn't kick in and the lights on the switch flashed. After some trial, we finally got it into 4lo. We got it back into 2WD, got it home and put a new switch in on the dash. The new switch won't light up, but it does have power to it and no fuses are out.

    I was thinking the new switch could be bad, but I also think maybe there's another problem such as the actuator on the t-case. Anyone have any thoughts?
     
  2. Catfishboy1995

    Catfishboy1995 New Member

    Messages:
    3,104
    State:
    Council Bluffs
    my moms 99' suburban was doing the same...i was driving and i didnt need the 4H any more so i tried to put it in 2H and the t-case locked in but the light didnt so looks like were having the same probleme just not the not locking in..try putting in in neutral and see if it works...
     

  3. texasaggie23

    texasaggie23 New Member

    Messages:
    35
    State:
    Texas
    We've tried to put it in neutral. Before at least something lit up, now there's nothing. I can't figure it out what's goin on. I have no clue as to your problem either. I thought i knew everything there was to know about 90s chevys until now... haha
     
  4. jrgriffhusker

    jrgriffhusker New Member

    Messages:
    722
    State:
    Minden, Nebrask
    I'm a firm believer and been a long time owner of Chevy's and the only way to switch them into 4wd is to put it into Neutral first. I know they say it's a switch on the fly but if you do that you'll wear the actator out way to fast. But I think that is a fairly easy fix if it does go bad.
     
  5. texasaggie23

    texasaggie23 New Member

    Messages:
    35
    State:
    Texas
    Yeah man, i definitely agree with you, my brother doesn't always treat everything great though... Yeah, I think its a pretty easy fix, I just wanted a little imput from someone else before we get a new one since its 150 bucks

    Thanks
     
  6. catman-j

    catman-j New Member

    Messages:
    1,020
    State:
    Eastern Nebr
    It could be the 4wd control module too. They are located on the passenger side next to the passenger foot are behind the trim on a blazer/jimmy. You might also check the light bulbs in the switch.
     
  7. Also try backing up 20 ft or so, this helps to disengage also. But it sounds like an electrical issue. Start with the simple stuff first bro. The fuses, the harness and connections. Shouldn't be too complicated. You got a manual for the truck to show ya a wirning diagram?? Most manuals do. Get the test light out if ya find that diagram and start tracing hoss. Keep us posted. Is that a 1/2 ton?
     
  8. Now that ya got me all curious, I did a little investigating, and it sounds like electrical. Apparently the different switch modes send a different resistance of electrical current to the T-case depending wich mode you select. Also looks like there is something called a "Transfer csae encoder module" that recieves the signals from the switch and actuates the T-case. It runs around $500.00 bucks. I read the first two pages of this thread. Sorting through the ramblings, there is some good info in there.

    http://forums.trailvoy.com/showthread.php?t=35306
     
  9. SkipEye

    SkipEye Well-Known Member

    Messages:
    7,525
    State:
    Winfield, MO
    Name:
    Darryl
    Did you put a NEW switch in?

    I am asking because I had a '99 Silverado. These trucks were notorious for 4wd switch problems, there are a ton of threads on this topic on the GM forums.

    I even had the same issue myself and it is an EASY fix.

    Take your switch apart and look at the back of the circuit card. You'll probably see some CRACKED solder joints. Re-flow the connection and you are good as new. It worked for me!