Service 4x4 light comes on 2000 Z71????????

I just bought a 2000 Z71 107,000 miles off Ebay. I had someone there drive it and check it out. All seams fine.. I buy it and the owner drives it 800
miles to me in Tenn. from Minnesota.. Looks sharp very clean.. I drive it does fine I pay him.
Now I'm taking him to the Memphis Airport.. I have been driving a 65 miles now the Service 4x4 light comes on.. It stays on, I ask him what is this? He tells me I swear it did not come on the way down here. He tells me it has come on before in the summer but goes off when you cut it off. He said he changes the front and rear 4x4 oil at 20,000 miles. He has done it twice since he owned it. I'm sorta of pissed now.. Now, when looking at the 4X4 strip the yellow light by 2x has gone off.. I tell him look I have bought it you come clean on this what needs to be done? He tells me the 4x4 works fine I used it in Iowa the light is nothing I swear it will go off when you cut off and back on..
Ok I have to realize I bought it in good faith and must not get to damn mad. This could be worse.. Ok we pull up to the AIRPORT, he says ok cut it off.. I do and wait about a min.. I cut back on and the light does not come back on... I put in 4x4 low and it locks in I go back to 2x high.. I tell him Ok fine. He gets out now I go back home 110 miles.... The LIGHT DOES NOT COME BACK ON.. hot damn... That was 3 days ago and it has not come on again.
Can anyone help me or know what it might be??
Thanking you guys in advance Toby T
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I had the exact same thing happen to me on my '04 Avalanche Z71at 30,000 miles when I was going out hunting last fall. Light came on whn I started it up in driveway, so I try the 4x4 system and sure enough, it would not engage. Great, I thought. Drove to fuel up, shut off for 5 min, restart, light is still on and 4x4 not working. I go out shooting birds anyway( not a muddy or wet day luckily). Get out in the bush, park the thing, take my 12ga out and go for a walk looking for birds. 25 min later back to the truck with a few Ruffies, and like magic when I start no warning light and 4x4 system works. And it's worked ever since. No stored codes when I got it home (I have a scanner). I attribute it to the GM electrical gremlin gods. I had a new '94 Suburban K1500 before the Avalanche that decided to stop working all the power windows 3 times over the 12 years I had it, which "cured" on next start. The cruise control would do similar things over the years. Go figure.
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I thought eBay had an insurance plan on purchased vehicles.
--
please reply to bargerw NO @ SPAM bellsouth.net and remove the NOSPAM


"Toby" < snipped-for-privacy@usit.net> wrote in message
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My 2000 Silverado used to do a similar thing. Mine used to flash SERVICE 4X4 when the vehicle was first started and then go off in 5-20 secs. During the time the light was on, I had no 4wd. Mine had a faulty push button dash switch. I believe there was a TSB for this but mine was under warranty so it was replaced free. I believe the switch is about $80 at the dealer but don't hold me to that one. Not sure if your issue is the same, but I believe these trucks had bad solder joints on that 4x4 selector switch.
HTH,
Derek
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Toby wrote:

This is a well know PROBLEM for the 2000 full size Chev models.
Prob is cold solder joints in the 4 button Push button assembly.
Either pull & resolder the bad joint or joints.... or buy a New $55 dollar push button switch assembly.
Mine was replaced under GM warranty in year 2002 for my 2000 Silverado 4x4 LX.

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It could be a sensor also that might be going. My Camry had the light go on and off for about 2 months before staying on. It was the o2 sensor. I would definitly suggest getting the computer to plug in and check what the light is on for. It's only about 60-80$ and since the dealer charges about 80$ to hook theirs up, it's well worth it.
Bill Cain

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