Service 4WD light

I have a 1999 Chevrolet P/U, Z71, automatic trans, 5.3L engine.

I recently began to notice that when I start my truck, all 4 lights (2WD, NEUTRAL, 4HI, and 4LO) light up, then I can hear 3 quick "tick" sounds (like tapping a ball point pen on a piece of metal), the "Service 4WD" light appears in the message center for about half a second, then it disappears, and then it seems fine with only the 2WD light on. It only does this when starting the vehicle and it doesn't do it every time ... maybe 2 out of every 3 starts.

Any ideas as to the problem? Thanks ...

Your 4WD switch is going bad. Easy fix...go to the dealer...it's like 50.00 dollars.

Or, pop off your dash trim piece, remove the 2/4WD select switch, take it apart, resolder the pins...when I did this to mine I had two that the solder was cracked...reinstall and save 50.00. Even if you bought the switch you would have to remove the old one so why not try to fix it yourself. If you can solder that is.

I get a 4WD service light in the message center of my 99 z71. i just bought this truck a month ago - please tell me it isn't an expensive problem... it comes on when i am driving in normal 2wd mode... help!

like they said up there, it is like 50-60 for a new switch, or you can solder your, but then you have a canch of burning it or melting it, if so then you just go get a new switch.