Cpdad93

My 97 is locked in four low. It got a new actuator on front axle about a year ago. I believe it is the switch, but not sure. #17 fuse under hood is good. It switched once from 4 low to 4 high, but the switched backed to four low only and is stuck there. I unhooked the actuator and manually clicked the hubs out so I get get it to quit wheel hopping to turn it around. Since the transfer case and front end would not disengage, I assume neither is getting signal or vacuum. Advise on steps to check switch? Will auto enginuity pick up the problem? Thanks, Don

mbb

Your front end doesn't matter really.... With it connected the drive shaft spins.... No big deal. .. with the axle disconnected the Axel's still turn and the spiders spin around the pinion. It's almost negligible power loss if your front drive shaft is spinning also. ..... Only your transfer case matters..... You can remove your shift motor, and turn the stub by hand/pliers to shift your transfer case to two wheel drive. It's three small 10 mm bolts and takes about 5 minutes.

You are aware you have to be in neutral to shift out of low right???? Shift on the fly doesn't apply to low. .......

Assuming you have ESOF......

manicmechanic007

If you are lucky, you can replace the 4x4 shift motor and it will work to shift itself out of low range and back to 4x2
Unlucky and you need a transfer case overhaul with a new low range shift fork
That happened to my 97 and I had to replace the T case
Mine absolutely would not shift out of 4 low with pliers.

Cpdad93

I have the panel off of the dash. Is there a way to check the switch to see if it is sending signal to the transfer case? Looks like the TC has 5 or six wires going into it. I checked all of my fuses and relays and they are all good, but not sure if it’s related but I do not have power to my windows either but do have power to door locks. Thanks, Don

manicmechanic007

Yes, there is a way
it requires a NGS that can read all the PIDS
There is a PID for each switch position and shift motor plate positions
That is so costly to do tha actual diagnosis, that most opt to just replace the shift motor
That solves 99 percent of the problems anyway
Like one of the above posts mentioned, pull the motor and see if the T case shifts okay manually
Then replace the motor and see if it works
Plan on about 450 at the dealer to get it properly diagnosed

mbb

Not really
The signals and switch go thru the GEM
When you start vehicle, it performs a self-test of the esof system
If anything is wrong.....its disabled by the GEM
So its pretty definite your switch isnt working...whether its the issue or not...and its probably not....

This makes it kind of hard to function test to identify the problem.... It's just not that simple.

Most common is bad shift motor, bad (wet) gem, bad wire (chafed and shorted or broken) Mechanical switches are fairly reliable when they're used infrequently, and not subject to corrosion.

A code is stored in PCM.......forscan may read it