'04 Silverado 4wd?

[Stratosman]

Okay here's one, hopefully someone here has run into this one before.

Stick with me. Everyone knows the switch I'm talking about, on the left of the wheel. 2WD, 4HI 4LOW and nuetral...anyway, lateley I've been getting a "service 4wd" prompt on the dash. Sometimes the light on the switch is where it should be, 2wd. Other times when I start it it's not on any level, sometimes nuetral and sometimes 4wd, (truck won't be in though).. And at any of these times I cannot engage into 4wd, however, if I turn off the truck and restart, as long as the light is on 2wd, I can engage into 4wd, and disengage as well. It's when the light is haywire or when the prompt shows up that I cannot...

Anyway, is this a problem with the switch or something else?

[LMITOUT]

I would guess it is the switch. If I recall they had some issues with the selector switch.

[federline]

Most likely. I have the 1999 new body style, same deal I experienced. I procrastinated, put it off, etc etc etc. Then I bought the part at the dealer (not expensive), took 20 minutes going slow to replace, it was a harness plug and a snap-in deal after the dash bezel is off.

[jwhjr]

The switch going bad is pretty common. That could be your culprit.

[Stratosman]

Okay, I put in the new switch and after about 5 minutes the service 4wd light came on, the same thing happens...I knew it couldn't be that easy. Any other ideas....???

Thanks...

[Scott K]

There is a tsb for this concern. It has you checking the wiring harness. TSB # 05-04-21-003b

[Scott K]

Stratosman check your email

The email didnt go through.

[Stratosman]

Thanks, I sent you an e-mail.

[Scott K]

Email sent back!

[MonsterMechanic]

First, you have to find out what codes are being set. A small generic scan tool that the parts stores use may not do the trick. You will need a scan tool that can communicate with all the modules on your truck to retrieve the codes. There is that TSB # 05-04-21-003b, which is related to the wiring harness, but I rarely find that to be the problem. It is very common to have a failed Encoder Motor(located on the Transfer Case) or a failed Transfer Case Control Module(located under the dash). Start with finding out the codes and reply.

[Stratosman]

Okay thanks...either way that's not something I will do myself...about as far from mechanically inclined as it gets...that leads me to my next question. Anyone know of anyone that can do this stuff on the side or something? Reasonably priced of course...

[email protected]

Thanks.