99 Silverado 4WD Kaput - Quit working

MTboatguy

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Was coming back from town yesterday, stopped at the mailbox, lights on the 4 wheel drive switch flashed, then no joy, truck stuck in 2WD I have never worked on a electronic 4WD Chevy system, so don't even know where to start. This is an all electronic system, when the lights went out, the Service 4WD warning indicator came on and glowed steady.

Any of you guys with Chev's had this happen?

99 Silverado 1500, 4WD, ABS Electronic shift 4WD, 4 speed auto trans.

Any help appreciated.
 

Scott Danforth

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check the actuator motor on the T-case.
 

wrench 3

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I don't know if it's what's happened to yours but they had a habit of building up corrosion between the transfer case and the actuator housing. The pressure would break the actuator motor housing.
 

gm280

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Just remember, even "electronic" controlled systems still has to have mechanical movement going on to work. That said, every type electronic setup has to have either solenoids or little motors to do what you would do without the electronics. So it seems overwhelming, but it really isn't once you get looking into it.
 

Scott Danforth

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just google silverado transfer case actuator.... its a simple system
 

MTboatguy

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I am aware it is not a complicated system, but there is 3 main electronic points in it and I was just wondering if there is a certain one of those items that are a common item to stop working.
 

Scott Danforth

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the actuator motor can is one of the most common failures, wiring is the second. there usually is a trans or BCM DTC which can be read by the Tech 2 or the snap on scan tool. a simply OBD code reader wont read anything except engine DTC's

FYI, the DTC's get you in the neighborhood, visual inspection and testing will be required.

https://www.motor.com/magazinepdfs/062004_07.pdf
 

MTboatguy

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MTboatguy,did you figure it out?

Not yet, I have not been able to get it home yet, I had to pick up a new set of chains for it, it is sitting at a buddy's house right now and I will go down and put the chains on it and get it home in the next day or so, so I can start the diagnosis it and see which part went bad..

:blue:
 

gm280

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MTboatguy, keep us updated, I am interested in what you find... But be careful as well...
 

MTboatguy

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MTboatguy, keep us updated, I am interested in what you find... But be careful as well...

Thanks guys, I will just not real interested in going out and fixing it right now, it is below zero, we have got about a foot of snow this last few days and we have had heavy winds, so it is quite uncomfortable outside right now.
 
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