4x4 not working

[BigBoomer]

Update.... now working.

It's fixed!!! Took advantage of the breaking in the weather yesterday and worked on it. Started checking the wiring again everything looked good so I decided to replace the shift motor. Put it back together kept my fingers crossed started it up no Service 4wd light and I now have 4wd again. I still have the noise when in 4wd but at least I have it fixed for now. Just in time too as we now have 3+ inches of snow and counting. Thank again Sunlit.

 

[SunlitComet]

 

[kphdrummer]

Hi there, I came across your thread on here this morning and I hope that you are still a member on here and willing to help me out!! I saw you were going to receive a paper manual for the 1996 Tahoe 4x4, and from what I could tell it is about the manual shifted 4x4. Mine is not where you press the dash buttons and hope it goes into four wheel drive. Well I thought I had a better system......Long story short, anytime that I try to engage the 4x4 it blows the fuse. Where can we start?? Thank you in advance for any help that you can give me!! Oh and that is low or high gear.

Kevin

Hey Boomer, I got that data for 98-99 models I was was hoping for and you are actually on the right track go for you wires and motor. Let me know if you want more info on the system.

---------- Post added at 07:23 AM ---------- Previous post was at 07:22 AM ----------

Bsamoul, my offer still applies for documentation for you if you have a fax. You never responded to my last post in another thread about that.
I will have in the next two weeks the original 1996 4x4 system paper manual which should also cover a few more years accept auto 4wd but I should have a alldata subscription for that and applicable model year vehicle service manuals maybe thursday.[/QUOTE]

---------- Post added at 05:11 AM ---------- Previous post was at 03:45 AM ----------

I have a 1996 tahoe 2 door, but my 4x4 switch is in the floor.Everything I am reading talks about an electrical switch on the dash, Can you please help me at all?

Thank You!
Kevin

Use this link and seperate text below to help you.

http://www.justanswer.com/uploads/MCVGreg/2008-02-15_210716_1998-Tahoe-C0323-Debug.pdf


C0308

NVG 236/246-NP8 Two-Speed Automatic



Circuit Description
The transfer case motor is a bidirectional, permanent magnet, D.C. motor. When energized, (through Motor Feed A or Motor Feed B. the ground is provided by the opposing Motor Feed circuit and then grounded through the transfer case shift control module ground circuit), the motor, through a series of gears, rotates the sector shaft which moves the mode and range forks to shift the transfer case between 4H, AUTO 4WD, 2H, N. and 4L ranges. While the transfer case motor is energized the transfer case shift control module also energizes the solenoid for the transfer case lock. The motor lock is disabled (locking action released) and free turning of the transfer case motor and sector shaft is then allowed.


This DTC detects a short to ground in Motor Feed A or Motor Feed B CKT.

Conditions for Setting the DTC

* The system will test the motor circuits:
* First, the system checks for unwanted voltage.
* Then, the system supplies voltage on one circuit and reads the voltage back on the other.
* If the system detects a problem with the circuits, the DTC is logged.
* The transfer case shift control module senses a low voltage return in Motor Feed A or Motor Feed B when a high voltage is expected.

Action Taken When the DTC Sets

* All shifting will be disabled.
* The SERVICE indicator (4WD/AWD) lamp will be latched on for the remainder of the current ignition cycle.

Conditions for Clearing the DTC

* The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists.
* A history DTC will clear after 100 consecutive ignition cycles without a fault present.
* History DTCs can be cleared using a scan tool.




Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
Listen for an audible motor noise when the encoder motor operates. Command both the ON and OFF states. Repeat the commands as necessary.

3. Tests for a short to ground in the Motor Feed A circuit.
4. Tests for a short to ground in the Motor Feed B circuit.
5. Tests for a higher than normal resistance in the Motor Feed A and B circuits through the module.
6. Tests for a short to ground in the encoder motor windings.
7. Tests for continuity across the motor circuit. Resistance readings vary depending on the location of the brush contact inside the motor assembly.
8. Tests Motor Feed A circuit for a short to ground.
9. Tests Motor Feed B circuit for a short to ground.
10. Tests Motor Feed A and B circuits for an open or high resistance.

 

[SunlitComet]

which fuse specifically?

---------- Post added at 07:48 AM ---------- Previous post was at 07:48 AM ----------

and what year do you have?

---------- Post added at 07:49 AM ---------- Previous post was at 07:48 AM ----------

and you have a floor shifter right.

 

[kphdrummer]

My Fuse

which fuse specifically?

---------- Post added at 07:48 AM ---------- Previous post was at 07:48 AM ----------

and what year do you have?

---------- Post added at 07:49 AM ---------- Previous post was at 07:48 AM ----------

and you have a floor shifter right.

Hi there, It is fuse # 24 for the 4X4 on the 96 2 door Tahoe. And yes it is a floor shifter. I hope this is enough info, I will be checking my e-mail today to see if you need further info from me.

Thank you so much for your time and effort!
Kevin

 

[SunlitComet]

try replacing the switch on top left of t-case or actuator on front axle but disconnect front axle connectors first and with a new fuse, engage it, does the fuse blow again?