2000 Blazer automatic. If I turn the truck off while in 2HI when it restarts it is in Auto 4x4 or 4HI. I do not believe it has actually switched while driving. Recent transmission rebuild, may not be related but I did not have this problem before. Is it safe to drive? Suggestions appreciated. Did my research here on the forum but found nothing like this. Thanks and best regards. Phil

PS Checked it out today and it does change to auto or 4HI while driving.

 

Hope you don't mind me moving this back to the top, still need some input.

Regards

 

I have the same problem I would be interested to hear too.

 

Problem persists. Any solutions?

Regards, Phil

 

Bad switch. Bad TCCM. etc...

What testing have you done? Have you had the TCCM scanned for codes?

 

Sorry I did not follow up, Thanks for the advice. For now I have unplugged the wire to the vacuum fitting on the firewall. The light on the switch still changes from AWD to 2HI by itself but since the vac switch is unplugged it doensn't make the transaction.

Regards

Phil