Periodic "Service 4WD" Light on Z71

HEY Everybody! I've got a 99 Z71 5.3L Check it: Every once in a while i'm just mosying along and me "Service 4WD" light pops on. I turn the truck off and the light stays off, for a while that it. THe light seems to turn on just every once in a while. Is that a bad switch or does it seem like a more serious problem? I love my truck, I just dunno what i'll do if its serious. I met my first two wives in collisions with this truck. Well, no, i'm not married to both of them at the same time. Awww heck, you know what i mean. THanks for your responses!

I had the same thing happen to my 00 z71. It is the 4wd select switch that is bad. Easy fix. You can purchase the switch at your chevy dealership for $52.00, pop off the front dash, unplug the old one, and plug the new one in. I did it in september of 03 and it has solved the problem.

Chance's are the fliud in your transfer case is low this will put the light on. Just change the fluid make sure you use autotrak-2 from GM if it is a 1999 nbs with push button 4x4 don"t use dexron. The price is $6.00 a quart\litre you will need 2.7 litre's. Hope this help's

Same thing happened to me also. It was also my switch. They said they had a bunch of them go out.

I don't know how much it costs cause it was under warranty. I bet you that is what it is.

I had my switch installed at a GM dealer last year for $10 plus parts. Total cost, about $65.

Change your switch.....guarentee it will fix it.

Okey dokey, sounds like the switch. THanks for your help. OH! also, does anyone know how long that switch would be under warentee? I've almost hit 60k on my 99 SIlverado.

If you bougt the truck new, I think most waranties last until like 50 or 75K. Mine was on 65K when I had mine replaced, but mine was also purchased used.

Hi. I'm interested in replacing my 4wd switch. Rumor has it that it's very easy to do. I'm just not sure how to go about it. Do i pop the actual switch thing away from the dash or do i have to take off some dash pannel? Does that thing really pop out pretty easy? Is it the selector switch with the lights and stuff or is it some other part? Thanks for your help.

I had the same problem in my 99, the switch is easy to get out, takes about 5 minutes, the hardest part is getting the connectors off. You can fix the switch yourself easy enough. After you get the switch out take it apart "carefully" and you will see that the problem is cracked solder joints on the connector pins. Resolder them and put everything back together and you are on your way. Took me 10-15 minutes to take it apart solder it and put everything back together, no problem since.

Lance

Wagslick, all you have to do is pop the plastic bezel that surrounds your dash off with a flat-head screw driver, then just wiggle the 4wd selector switch assembly out. Too easy, good luck. Oh yeah, by the way, my factory warranty expired at 36,000 miles, about 5,000 miles before the "service 4WD light would come on.

I had the same problem in my 99, the switch is easy to get out, takes about 5 minutes, the hardest part is getting the connectors off. You can fix the switch yourself easy enough. After you get the switch out take it apart "carefully" and you will see that the problem is cracked solder joints on the connector pins. Resolder them and put everything back together and you are on your way. Took me 10-15 minutes to take it apart solder it and put everything back together, no problem since.

Lance
I fixed my switch by resoldering the pin connections to the circuit board, you can check this with some sort of magnifing glass and carefully check for hair line breaks around the factory soldering joints, resolder and presto it works great
Richard

I had the same problem on my 2003 Suburban, the dealer stated it was in need of a computer update? The warning was gone when I got it back. I noticed that when the service 4WD was on the DIC, that no lights were on the selector panel > Strange! All is well now

How often is the computer in need of an update? Are they free from the dealer once the warantee expires? I have 2001 Silverado, does it need the same updates?

computer update on my 03' seemed to fix it also.

In the immortal words of Gomer Pyle "Well I'll Be, Thank You, Thank You, Thank You" I too have a K1500 with the "Service 4WD" light on but not anymore. Last night I read the posts in this thread and went out to my truck with a flashlight to pull the selector switch. After taking the switch apart and looking at the solder connections I noticed several that were cracked. After resoldering them and driving around with the repaired switch not once did the "Service 4WD" come on. Thanks guys, you saved me a trip to the dredded dealer. They probably would have wanted to rebuild the carburetor.

Did the same to mine last week. Haven't seen the "service" light since. Also this is the second switch, one was replaced under warranty. I think this switch had solder joints cracked from the start because it would not shift the transfer case to neutral by holding in the 2wd and 4lo buttons together. After resoldering that works too.
RDS