Last post on Dec 21, 2009 at 5:12 PM
You are in the GMC Jimmy
What is this discussion about?
GMC Jimmy, SUV
#32 of 41 Re: Stuck in four wheel high problem [dougaroo]
Jan 03, 2007 (2:46 am)
Yep, a pain and good its fixed. Dorman makes new encoders and has pictures online - under $250 at most auto stores - many will order them for you and then rockauto and gmpartsdirect are 2 online ones. Sorry, a day late and a few dollars short.
#33 of 41 Re: 99' Chev Blazer 4x4 will not engage? [jackassjay]
Oct 30, 2007 (5:45 pm)
My 99 blazer does not respond at all.No lights or anything.
In shop getting diagnosed tomorrow.
Will let you know what they find.GM junk again.
#34 of 41 Re: 99' Chev Blazer 4x4 will not engage? [murphy51]
Nov 05, 2007 (6:46 pm)
Found a blown fuse under hood in fuse box.Replaced and worked for a while and blew fuse again.Must be a short somewhere.
#35 of 41 Re: Encoder Motor Problem for 97 GMC Jimmy [repairdog]
Nov 05, 2007 (6:49 pm)
Mine keeps blowing the fuse under hood in the fuse box.Any ideas?
#36 of 41 Tranny fluid in vac hose
Dec 12, 2008 (1:59 pm)
2000 GMC Jimmy 4x4 4.3, VIN "W". I'm swapping a tired engine/tranny with a another used one (what a pain!!!) and when I removed the hose to the 4x4 front axle engage vac motor several ounces of tranny fluid ran out of the motor. I also noticed tranny fluid in vac hose when removing the three port connector to the vac valve on top of the transfer case. I assume the seal inside the valve has failed and sucking fluid. Does that sound likely? Will the tranny fluid ruin the vac motor, should I replace that also? Also, any known problems to look for, or parts to replace before re-installing, e.g. timing chain, water pump, etc? The "new" engine/tranny has 47,000 so it should be OK for a while.
#37 of 41 Re: Tranny fluid in vac hose [Rick_M]
Dec 15, 2008 (8:13 pm)
Well I investigated a little further and figured it out myself. Since the fluid in the transfer case is green and the fluid that ran out of the vac motor was red, I knew it was not the vac switch on top the transfer case. It had to be tranny fluid, so I traced out the vac lines and found that the vent line from the tranny has a tee in it that connects to the vent port on the transfer case vac switch. The only thing I can figure is at some point someone must have overfilled the tranny and it filled the vent line. Then when the 4x4 was activated it sucked the tranny fluid that was in the line into the vac motor when it disengaged. The only other thing that might caused it was if the tranny fluid foams and fills the vent tube.
To prevent that from ever happening again I ran a seperate vent for the tranfer case.
I also replaced all of the vac hoses from the transfer case vac switch all the way to the intake manifold. Several sections was already soft from the tranny fluid. I also ran a new line to the vac motor under the battery tray.
Oct 24, 2009 (5:40 am)
i read alot of the post's about the problems of failed 4x4, mine was stuck in 4x4 for awhile and always thought it was a cv joint, i finely got it out of 4x4 but i found there was that atc blown fuse, put a new one in and it blew, i got to the tccm and checked the wires, did seem fine, i plugged the little cable in first and the fuse did not blow, hooked up the big one and pop, where is a good place to check. i have checked wires and seem good, i did not drop the gaurd under the encoder motor to check anything there, help would be appreciated.
thank you all
#39 of 41 Re: 99 jimmy 4x4 [michael79]
Oct 26, 2009 (3:41 am)
ok men, thank you, i think i read enough to understand that most likely it is the encoder motor. if not, i'll be back.
#40 of 41 Re: 99 jimmy 4x4 [michael79]
Oct 26, 2009 (4:26 pm)
i did find a bare wire under the brush guard that goes to the encoder motor, next to the connection it was rubbing on the shaft, going to the shop now they help me out, can not do it laying down with my neck. you all have given alot of insight for this problem. thank you
#41 of 41 Re: Encoder Motor Problem for 97 GMC Jimmy [repairdog]
Dec 21, 2009 (5:12 pm)
I am trying to repair my "encoder issue" by disconnecting my battery right now. However, I think this may not be the fix because reading everyone's post, my issue may be a little different. My 4Hi, 4LO, and 2Hi all work. Except what happens is that every so often the red light next to my Neutral, in between 4Hi and 2Hi, lights up, and when it lights up I cannot control whether I am in 2 wheel drive or 4 wheel drive. The dealership said it was my encoder and wanted $700+. Any other insight, or still feeling its either the encoder motor, encoder sensor or fuse? Thanks.