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4wd Service On Again!

kelch420

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kelch420 Enthusiast

kelch420

Posted
Posted

Hey guys I just replaced my 4wd switch 2 days ago, because I was getting the "Service 4wd" message. I would push Auto 4wd but the light would just flash and the 2wd light would stay on, so I replaced it. I installed the new one and it worked all day yesterday, and now it is doing the same thing as it was before! Now I just need to know what else it could be. I think I might have to bring it to the dealership now....

 

It is a 2007 GMC Sierra Z71.

lvlagnum Enthusiast

lvlagnum

Posted
Posted

Sounds like a situation I had with my '03 Silverado. I thought it needed a new switch but when I took it back to the dealer to be repaired under warranty, they said all it needed was to have the PCM reflashed with an update. They reflashed it and I never had that problem with it again.

 

Cheers, lvlagnum. :D

C. Charles Hahn Senior Enthusiast

C. Charles Hahn

Posted
Posted

Yup, could be a computer issue or it could be a stuck shift solenoid... I had that issue in the past on a vehicle and it behaved similarly to what you describe.

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