Tip & How-To about Chevrolet Silverado 1500

2006 Silverado won't stay in 2wd or 4wd not working.

On the transfer case there is a module that shifts the transfer case for you. This happens to go out at about 70,000 - 120,000 miles. If you are having problems with the electronic 4wd this is probably the problem.

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How do you change out 4 wheel drive switch on 2004 Yukon


Before trying to replace the switch ,are any lights flashing ? 2hi , 4lo, 4hi etc... Do you know which transfer case yours has ?
Transfer Case - BW 4482-NR4
Transfer Case - NVG 246-NP8
How many buttons ?
The BW 4482 transfer case features a 3-button shift control switch located on the instrument panel.
The NVG 246 EAU transfer case features a 4 button shift control switch located on the instrument panel
Before you replace the switch and finding out that it isn't the problem . The switch is a low voltage input to the tansfer case shift control module (A COMPUTER ) Could have diagnostic trouble codes stored .
DTC B0790
DTC B2725
DTC C0306
DTC C0327
DTC C0329
DTC C0359
DTC C0550
Auto part stores can not read these codes .

The BW 4482 transfer case features a 3-button shift control switch located on the instrument panel. When the vehicle has the ignition key in the RUN position, the transfer case shift control module starts monitoring the transfer case shift control switch to determine if the driver desires a new mode/range position. At a single press of the transfer case shift control switch, the lamp of the new desired position will begin flashing to inform the driver that the transfer case shift control module has received the request for a new mode/range position. The lamp will continue to flash until all shifting criteria have been met and the new mode/range position has been reached, or has been engaged. Once the new mode/range position is fully active, the switch indicator lamp for the new position will remain ON constantly. In addition, the switch includes a VSES request button which sends a voltage signal to the transfer case shift control module. The transfer case shift control module in turn sends a request via the class 2 data bus to the ABS control module which controls the VSES system.

The NVG 246 EAU transfer case features a 4 button shift control switch located on the instrument panel. When the ignition key is in the RUN position, the transfer case shift control module monitors the transfer case shift control switch to determine if the driver desires a new mode/range position. At a single press of the transfer case shift control switch, the lamp of the new desired position will begin flashing to inform the driver that the transfer case shift control module has received the request for a new mode/range position. The lamp will continue to flash until all shifting criteria has been met and the new mode/range position has been reached, or has been engaged. Once the new mode/range position is fully active, the switch indicator lamp for the new position will remain ON constantly.
DTC B2725
Circuit Description
The range/mode switch circuit consists of 5 modes. The transfer case shift control module supplies 5 volts to the switch through the 5 volt reference circuit. The current travel through the resistor of the currently active mode. The current is then returned to the transfer case shift control module through the switch signal circuit.
The transfer case shift control module constantly monitors this signal voltage to determine the condition of the mode switch circuit.
When each of the modes are selected they complete a circuit through their own specific resistor. The transfer case shift control module continuously monitors the switch input to determine whether the Neutral, AWD, 2HI, 4HI, or 4LO mode was selected by the driver.

You may want to take this to a repair shop .

Jul 28, 2017 | Cars & Trucks

1 Answer

1998 chevy blazer four wheel drive not engageing


You replaced all those parts without knowing what is wrong , you like making parts stores rich ? Did you have it checked for DTC'S - diagnostic trouble codes ?
Transfer Case Control Module Description
The TCCM performs the following functions:
• Receives input signals
• Processes the signal information
• Develops output signals
• Sends the output signal in order to control the shifting of the transfer case
The TCCM receives input signals from the following sources:
• The transfer case shift select buttons
• The NSBU switch on the vehicles with automatic transmissions
• The clutch position switch on the vehicles with manual transmissions
• The vehicle sped sensor calibrator module
• The encoder/motor range and the mode feedback signals
• The diagnostic enable
• The front axle mechanical status signal
In order to ensure the electronic shift system is operating properly, the transfer case control module (TCCM) continually performs diagnostics checks on itself and other parts of the electronic shift system when the ignition switch is in the run position. The following are different types of system checks that the TCCM continually performs.

Motor and Relay Voltage Checks
Whenever the electric-shift motor is turned ON or OFF the motor and the electrical circuits are tested both in the de-energized and energized condition. If one or both voltage relays fail to detect the proper voltage after energizing or de-energized and energized condition. If one or both of the voltage relays fail to detect the proper voltage after energizing or de-energizing, the shift is aborted by the TCCM and a DTC of 3 is stored in order to indicate a faulty TCCM motor circuit.
If one or both relays fail to detect the proper voltage after de-energizing, both relays are turned ON by the TCCM, (even with the ignition switch positioned OFF) in order to prevent the motor from running. The TCCM then stores a DTC of 3 in order to indicate a faulty TCCM motor circuit. All of the status lamps blink three times, stop, and repeat the blinking continuously in order to alert the driver that the electronic shift system requires immediate repair. The battery will drain when this condition occurs, regardless of the ignition switch position.

DTC 001
DTC 002
DTC 003
DTC 004

DTC 001
The transfer case shift control module normally has battery voltage supplied to it at all times through the battery positive voltage circuit (CKT 40). When the ignition is ON, the transfer case shift control module conducts a self-test to determine if it retains the same memory it had when the ignition was last turned OFF. This self-test indicates whether the RAM standby power supply to the transfer case shift control module pin C6 was interrupted, which would result in clearing DTC's from memory. If the self-test fails the transfer case shift control module sets DTC 1.
Inspect the CTSY LP fuse for an open.

DTC 002
The transfer case encoder motor is an assembly which houses four separate channels. These channels are used to indicate to the transfer case shift control module the present gear position of the transfer case or if the transfer case is in transition between gears. The encoder motor assembly consists of an electronically conductive inner ground ring in contact with a three legged wiper arm. Each leg's length is such that it makes contact with the conductive regions of the four channels. When any leg of the wiper arm is making contact with the conductive area of any channel, the encoder provides a path to ground to the inner ground ring.
During electronic shifting, the transfer case shift control module monitors the transfer case encoder circuit for the proper operating sequence. If at any time during a shift, the encoder changes from one position to any position other than the next possible position, an error counter in the transfer case shift control module increments by four. After the counter reaches 32, the transfer case shift control module set a DTC 2, a permanent "encoder fault," and reverts to a 2HI to 4LO or a 4LO to 2HI shift pattern only. To guard against a transient, random encoder fault due to vibration, dirt, electrical noise, etc., the fault counter reduces by one each time the transfer case shift control module detects a valid encoder value. The encoder must intermittently fail 25 percent of the time for the transfer case shift control module to consider it faulty and store DTC 2.

DTC 003
Circuit Description
The transfer case encoder motor has a bi-directional, permanent magnet, D.C. motor. When energized, (through Motor Control A or Motor Control B, the ground is provided by the opposing motor control circuit and then grounded through the transfer case shift control module ground circuit), the motor, through a series of gears, rotates a shaft which moves the mode and range forks to shift the transfer case between 4H, 2HI, and 4L ranges.
This DTC detects a short or open in the battery positive voltage circuit (CKT 1640), ground circuit, an internal short in the motor windings and related circuitry, or an internal transfer case shift control module failure.
Action Taken When the DTC Sets
In the event that one of the motor control circuits is energized (battery voltage is applied) the transfer case shift control module will energize the other motor control circuit to keep the motor from running. All switch indicator lamps will flash continuously to prompt the driver that service is required. The transfer case system will be disabled and the transfer case shift control module will remain energized even with the ignition in the OFF position.
Conditions for Clearing the DTC
The condition for setting the DTC is no longer present and a momentary loss of battery power at the battery positive voltage circuit (CKT 40).
Diagnostic Aids
When the vehicle is equipped with a manual transmission the clutch pedal must be depressed and working correctly in order for the transfer case to shift to the 4 low position. In order to confirm that it is operating correctly go the engine data 1 screen under the engine data display and observe the clutch pedal switch parameter.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
This step tests the battery positive voltage circuit (CKT 1640) for an open or high resistance.
This step inspects the ATC fuse for an open.
This step tests the ground circuit.
This step tests the Motor Control A and B circuits.
DTC 3 -- TCCM Motor Circuit Step
Action
Value(s)
Yes
No
1
Important: Check the transfer case shift control module for DTCs. The transfer case shift control module is not a class 2 device. DTCs are displayed on the transfer case shift control switch. Use the following four steps to obtain DTCs.
Turn OFF the ignition for 10 seconds.
Connect PIN 13 on the data link cable (DLC) to a ground. The DLC is located in the cab under the instrument panel on the driver's side.
Turn ON the ignition, with the engine OFF.
Observe the transfer case shift control switch select buttons for flashing codes.
Did you perform A Diagnostic System Check - Transfer Case?
--
Go to Step 2
Go to Diagnostic System Check
2
Turn ON the ignition, with the engine OFF.
Backprobe and measure battery positive voltage (CKT 1640) at the transfer case shift control module.
Does the voltage measure near the specified value?
B+
Go to Step 6
Go to Step 3
3
Inspect the ATC Fuse 20A.
Is the fuse blown?
--
Go to Step 5
Go to Step 4
4
Repair the battery positive voltage circuit (CKT 1640) for an open or high resistance. Refer to General Electrical Diagnosis and Wiring Repairs in Wiring Systems.
Did you complete the repair?
--
Go to Step 11
--
5
Repair the battery positive voltage circuit (CKT 1640) for a short to voltage or short to ground. Refer to General Electrical Diagnosis and Wiring Repairs in Wiring Systems.
Replace the ATC Fuse.
Did you complete the repair?
--
Go to Step 11
--
6
Connect a test lamp from the battery positive voltage circuit (CKT 1640) to the ground circuit at the transfer case shift control module.
Does the test lamp illuminate?
--
Go to Step 8
Go to Step 7
7
Repair the ground circuit for an open or high resistance. Refer to General Electrical Diagnosis and Wiring Repairs in Wiring Systems.
Did you complete the repair?
--
Go to Step 11
--
8
Backprobe and measure voltage at the transfer case shift control module between the transfer case motor control A circuit and the transfer case motor control B circuit.
Press the 4HI then 4LO on the shift control switch.
The DMM should read +12V in one direction and -12V in the other direction.
Does the voltage measure near the specified value?
+12V/-12V
Go to Step 9
Go to Step 10
9
Repair the open or high resistance in the transfer case motor control A or B circuits. Refer to General Electrical Diagnosis and Wiring Repairs in Wiring Systems. If OK, replace the transfer case encoder motor. Refer to Motor/Encoder Replacement .
Did you complete the repair?
--
Go to Step 11
--
10
Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement .
Did you complete the replacement?
--
Go to Step 11
--
11
Clear all DTCs from memory. Refer to Diagnostic Trouble Code (DTC) Clearing .
Operate the vehicle while pressing each of the buttons on the transfer case shift control switch.
Does the DTC reset?
--
Go to Step 2
System OK

There is a bit more to it then just replacing parts ! Your best bet - Take it to a qualified repair shop .

Feb 07, 2017 | Chevrolet Blazer Cars & Trucks

1 Answer

I own a 02 foard explorer shift motor was bad i think and i removed it, i started it to relocate it, installed the new shift motor


Don's 1999 Ford Ranger shift motor PROBLEM SOLVED ...

? 13:05
https://www.youtube.com/watch?v=wcn39gwPWfI
Oct 1, 2013 - Uploaded by gtarman49
Don's 1999 Ford Ranger shift motor PROBLEM SOLVED. ...How to find replace fix 4x4 transfer case shift module 2002 Ford Explorer 4 wheel ...

How To Install Replace 4x4 Transfer Case Shift Motor Ford ...

? 9:15
https://www.youtube.com/watch?v=9ldrtZODxQ8
Oct 26, 2010 - Uploaded by 1A Auto Parts
How To Install Replace 4x4 Transfer Case Shift Motor Ford Explorer .... transfer case shift module 2002 Ford Explorer 4 wheel drive not working ...

How to find replace fix 4x4 transfer case shift module 2002 ...

? 3:07
https://www.youtube.com/watch?v=sZw3SS2Pt-4
Nov 3, 2013 - Uploaded by kirk colombo
... transfer case shift module 2002 Ford Explorer 4 wheel drivenot working ..... I replaced the transfer motor so i think it is the control module.


Jan 08, 2016 | Cars & Trucks

1 Answer

where is the transfer case shift motor located on 2004 dodge dakota


The transmission control module and the transfer case control module are separate parts. The transmission control module is mounted under the hood and controls only transmission functions. The transfer case control module controls only the transfer case, and is located inside the truck. If you remove the trim panel under the steering column you will find the transfer case control module mounted just to the right of the opening.


The shift motor is located just behind the axle tube to prevent damage.
There is a shift motor on the right front axle that is vacuum operated.
The shift motor (1) is an electromechanical device consisting of a DC permanent magnet motor, a motor brake, a gear train and an analog position sensor. The shift motors' overall function is to move and lock a gear that moves the mode fork found in the transfer case. This allows the transfer case to be shifted electrically to multiple operating positions (4LOCK and AWD). The operating current of the shift motor under
stall conditions is 30 amps maximum at 72° F with 13.5 volts, at the motor leads.
OPERATION
Shifting in the transfer case occurs when the shift motor brake is released and a Pulse Width Modulated (PWM) voltage is supplied to the shift motor by the Front Control Module (FCM). A linear analog position sensor located inside the shift motor, provides the FCM with the motors' angular, rotational position. With this information, the FCM
continuously knows the motors' position, and therefore allows it to accurately control the motors' operation, including voltage polarity which is used to control motor direction.

REMOVAL :---Note: New shift motor assemblies are shipped in the AWD position. If a new shift motor assembly must be installed, it will be necessary to shift the transfer case to the AWD position prior to motor installation.
Raise the vehicle on a suitable hoist.Remove the front propeller shaft. Disengage the wiring connectors from the shift motor and mode sensor.Remove the front output shaft companion flange from the transfer case.Remove the bolts (Remove the Shift Motor and Mode Sensor Assembly Bolts) holding the shift motor and mode sensor assembly onto the transfer case.Separate the shift motor and mode sensor assembly from the transfer case. See fig below:-- helpmech_19.gif
1 - TRANSFER CASE.2 - SHIFT MOTOR AND MODE SENSOR ASSEMBLY.3 - BOLT.-- This should help.Thanks.Helpmech.

Feb 26, 2011 | 2004 Dodge Dakota

1 Answer

transfer case grinds truck only runs in 4wheel low nothing in 4wheel high or 2wheel drive


Manual or electronic t case?

Section 07-07: Transfer Case, 4x4 System, Service 1994 Bronco/Econoline/F-Series Workshop Manual
DESCRIPTION AND OPERATION Electronic Shift Operation The transfer case is equipped with a magnetic clutch, similar to an air conditioning compressor clutch, which is located inside the transfer case adjacent to the lockup collar. The clutch is used to spin up the front drive system from zero to vehicle speed in milliseconds. This spin-up allows the shift between 2-high and 4-high to be made at vehicle speeds listed in the vehicle owner's guide. The spin up engages the front lock hubs. When the transfer case rear and front output shafts reach synchronous speed, the spring-loaded lockup collar mechanically engages the mainshaft hub to the chain drive sprocket and the magnetic clutch is then deactivated. Shifts between 4-high and 4-low can only occur with the transmission safety switches closed. The vehicle's speed must also be within specified limits as determined by the transfer case speed sensor (3 mph or under). Electronic Shift Control System
This system consists of a two-switch control system, an electronic control module, an electric shift motor (7G360) with an integral shift position sensor, and a speed sensor. Switch Control System
There are two control switches located on the upper right corner of the instrument panel for fingertip shift control. The two switches are mounted horizontally and are identified as "4x4" and "LOW RANGE". Two indicator bar lamps are located in the instrument cluster.

c11148a.gif

When either of the two switches on the instrument panel control are depressed, the first thing that happens is that the electronic control module receives input from the transfer case shift position sensor to verify what position the transfer case is in (2H, 4H or 4L). Next, the electronic control module looks at the speed sensor and the park/neutral position switch or clutch pedal position switch (depending on transmission type). If all conditions are correct to allow the desired shift, the electronic control module will tell the electric shift motor to execute the shift. After the shift has been made and the electric shift motor is off, the control module again looks at the shift position sensor to make sure the proper shift has been accomplished. Finally, the dash indicator light and the pushbutton light on the control panel will be illuminated by a signal from the electronic control module indicating the desired function has been completed.
Electronic Control Module
The electronic control module, located on the passenger side, controls the operation of the transfer case in response to inputs to the pushbutton control by the vehicle operator, the speed sensor, shift position sensor and the park/neutral position switch. Speed Sensor
The speed sensor, mounted on the rear of the transfer case , tells the electronic control module the speed of the vehicle to allow range shifts (in or out of 4L) to occur. Shift Position Sensor
The shift position sensor, an integral part of the electric shift motor , tells the electronic control module the shift position of the transfer case . Electric Shift Motor
The electric shift motor , mounted externally at the rear of the transfer case , drives a rotary helical cam which moves the 2W-4W shift fork and 4H-4L reduction shift fork to the selected vehicle drive position.

Nov 12, 2010 | 1994 Ford F250 Supercab

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