2001 Jimmy 4WD problems

I'll sum it up for you. 2001 Jimmy 4door 4WD, three button switch. I have been having problems with the car shifting from 2wd to 4wd high & back on its own. sometimes if it switches into 4wd it will not go back into 2wd right away if I push the button. I was told to try replacing the TCCM & the 3 buttom switch. I have replaced both and still have the same problem. Today I had a very loud howl,rubbing noise coming from the front of the car as I was driving it. I am guessing it was coming from the 4wd not engaging all the way, because when I pushed the 4wd high button it engaged & the noise went away. Any suggestions where I should look? Vacum leaks, acuator, cable, vacum switch? I'm at my wits end with and it is driving me nuts! Any help would be greatly appreciated.
I have read that the actuator is under tha battery tray, how do I test it if I have to take the battery out to get to it?


Thanks,
Steve

I'll sum it up for you. 2001 Jimmy 4door 4WD, three button switch. I have been having problems with the car shifting from 2wd to 4wd high & back on its own. sometimes if it switches into 4wd it will not go back into 2wd right away if I push the button. I was told to try replacing the TCCM & the 3 buttom switch. I have replaced both and still have the same problem. Today I had a very loud howl,rubbing noise coming from the front of the car as I was driving it. I am guessing it was coming from the 4wd not engaging all the way, because when I pushed the 4wd high button it engaged & the noise went away. Any suggestions where I should look? Vacum leaks, acuator, cable, vacum switch? I'm at my wits end with and it is driving me nuts! Any help would be greatly appreciated.
I have read that the actuator is under tha battery tray, how do I test it if I have to take the battery out to get to it?


Thanks,
Steve

Have you checked for transfer case codes by grounding pin 13 and counting shift button flashes?

On the shift on it own do you mean it shifts itself in and out or just does not want to shift?

What does the shift button lights do when you try to shift it?
Have you tried shifting in neutral or when it is rolling back or forward?

Are your tires a matched set and rear ends match up?

Is the front actuator getting good vacuum?
Does it lock in front axle good?

http://www.automotiveforums.com/vbulletin/showthread.php?t=572914

Have you checked for transfer case codes by grounding pin 13 and counting shift button flashes?

On the shift on it own do you mean it shifts itself in and out or just does not want to shift?

What does the shift button lights do when you try to shift it?
Have you tried shifting in neutral or when it is rolling back or forward?

Are your tires a matched set and rear ends match up?

Is the front actuator getting good vacuum?
Does it lock in front axle good?

http://www.automotiveforums.com/vbulletin/showthread.php?t=572914

It shifts on it's own without me touching it. when I try to shift the light on the switch flashes & hear the click in the TCCM but it doesn't shift. No I haven't tried shifting in Neutral or while rolling backwards. This problem general shows up very randomly. I will be driving down the road and see the 4wd lights flashing out of the corner of my eye and all of a sudden it is in 4wdhi. I push the button to get it back into 2wd the lights flash I hear the tccm click but it stays in 4wd hi. Then at some point it shifts back into 2wd on it own...

I have not checked the actuator yet or the codes, I will do that this weekend. if I have to take the battery & tray out to get to it how do I get the car running to test it? Tires are good and matched. when it locks into 4wd it locks good.

It shifts on it's own without me touching it. when I try to shift the light on the switch flashes & hear the click in the TCCM but it doesn't shift. No I haven't tried shifting in Neutral or while rolling backwards. This problem general shows up very randomly. I will be driving down the road and see the 4wd lights flashing out of the corner of my eye and all of a sudden it is in 4wdhi. I push the button to get it back into 2wd the lights flash I hear the tccm click but it stays in 4wd hi. Then at some point it shifts back into 2wd on it own...

I have not checked the actuator yet or the codes, I will do that this weekend. if I have to take the battery & tray out to get to it how do I get the car running to test it? Tires are good and matched. when it locks into 4wd it locks good.

Hook a battery up with jumper cables.
Post back any codes.
The code may poimt to the problem.

Look all wiring over and double check push button switch.

Post back any codes.

Will do thanks!

Will do thanks!

If it is shifting into 4W on it own I would unplug push button switch and see if it still does it with switch unplugged.
If not problem is in switch.
If so you have something shorting out.

Let us know how it goes.

will do thanks!

will do thanks!

Let us know what you find.

Finally had time to check for an error code. used a paperclip and jumped Pin 13 to pin 4 and got nothing. Lights turned on when I turned the key on but went out with no flash codes. I am starting to think my switch is bad time to order a new one. I'll keep you posted. It's frustrating it is such a random problem I haven't had it happen for 3 days, but when it happens it happens all the time LOL

Steve