Electronic Shift Motor issues

[Tilldain]

so i am working on my shift motor due to my 4x4 lights flashing both high and low at the same time i have printed the excellent rebuild thread and went thru that. when we apply direct power to the motor it will engage and reverse. when we plug it in to the harness and check power at that point. we are not getting it to engage. we are hearing a humming that is coming from inside the vehicle. not able to isolate this sound believe that it may be the shift computer. i have a 97 sport with the control trac AWD system. please post thoughts or comments

Thank you
Todd

 

[BrooklynBay]

Welcome to this forum! I see that you are new here. It sounds like the motor is running, but not engaging anything. That is also the reason why you are getting both lights on at the same time. There is a part that is supposed to stop everything when it reaches a certain point. That part is broken. You could replace that piece by adding a piece of rubber hose. Look through this forum for pictures of the inner workings, and where to put that replacement rubber hose stopper. There are several very useful threads with this information.

 

[gijoecam]

On the '97, the transfer case motor is not supposed to move for the 4auto-->4high shift. The transfer case uses an electromagnetic ball-ramp type of clutch that locks the front driveshaft to the rear driveshaft.

The blinking lights can be caused by a number of things, the most common of which is a bad speed sensor on the transfer case. No amount of monkeying with the motor is going to fix the blinking lights, unless the system simply doesn't know the position of the motor.

In these cases, I hate to suggest it, but it's sometimes worth it to pay the $80 diagnostic fee at the dealership to let them hook it up to the NGS tester and view the GEM inputs and outputs, as well as the stored trouble codes for the system. AutoZone will nto be able to access them. The dealer should be able to tell you in a matter of minutes where the problem is based on the code(s) they see.

-Joe

By the way, I assume that you have no 4 wheel drive, no aut, no high, and no low range, correct?

 

[Tilldain]

Thanks for the welcome you guys are great here very helpful and knowledgeable

so in response to my previous post and some of the other info what we did was disconnected the battery for some time to reset the computer and during this we reinstalled the motor and then checked the system it kicked into 4x4 and then backed out the shop and thru it in to 4x4 low and it took a sec but then kicked in to low drove for the last 3-4 days and on the way home tonight the lights started flashing again....Joe cam in response my auto does engage properly I can feel it when accelerating and it makes that awful sound of the front end getting power. completely lost at this point may take it to the dealer on monday to figure it out.

 

[gijoecam]

Sounds like a speed sensor is on the fritz.... that would be my guess anyways....

The dealership should be able to tell you in a matter of minutes....

-Joe

 

[Tilldain]

kind of sort of working

so after we got it working again the lights started to flash a couple of days later and 4 wheel would not engage again. dc the battery and low and behold the 4 wheel drive works again both high and low are full functioing as of right now with no problems. have been fine for about a week now.