sensor DODGE RAM SRT-10 2006 Service Repair Manual

TRANSFER CASE - NV243 - SERVICE INFORMATION
DESCRIPTION
The NV243 is an electronically controlled part-time transfer case with a low range gear reduction system. The
NV243 has three operating ranges plus a NEUTRAL position. The low range system provides a gear reduction ratio
for increased low speed torque capability.
The geartrain is mounted in two aluminum case halves attached with bolts. The mainshaft front and rear bearings
are mounted in aluminum retainer housings bolted to the case halves.
OPERATING RANGES
Transfer case operating ranges are:
2WD (2-wheel drive).
4HI (4-wheel drive).
4LO (4-wheel drive low range).
NEUTRAL.
The 2WD range is for use on any road surface at any time.
The 4HI and 4LO ranges are for off road use only. They are not for use on hard surface roads. The only exception
being when the road surface is wet or slippery or covered by ice and snow.
The low range reduction gear system is operative in 4LO range only. This range is for extra pulling power in off road
situations. Low range reduction ratio is 2.72:1.
SHIFT MECHANISM
Operating ranges are selected with a dash mounted shift selector switch. The shift selector switch provides a input
to the Transfer Case Control Module (TCCM) to indicate the driver’s desireto change operating ranges. The TCCM
uses this input, along with input from the transfer case mounted mode sensor and information from the vehicle’s
bus, to determine if a shift is permitted. If the TCCM decides the shift is permitted, the TCCM controls the shift
motor, mounted to the exterior of the transfer case, to perform the shift.
IDENTIFICATION
A circular ID tag (1) is attached to the rear case of
each transfer case. The ID tag provides the transfer
case model number, assembly number, serial number,
and low range ratio.
The transfer case serial number also represents the
date of build.
OPERATION
The input gear is splined to the transmission output shaft. The input gear drives the mainshaft through the planetary
assembly and range sleeve. The front output shaft is operated by a drive chain that connects the shaft to a drive
sprocket on the mainshaft. The drive sprocket is engaged/disengaged by themodefork,whichoperatesthemode
sleeve and hub. The sleeve and hub are not equipped with a synchronizer mechanism for shifting.

REMOVAL
1. Shift transfer case into 2WD.
2. Raise vehicle.
3. Drain transfer case lubricant.
4. Mark front and rear propeller shafts for alignment
reference.
5. Support transmission with jack stand.
6. Remove the transfer case skid plate, if equipped.
7. Disconnect front and rear propeller shafts at trans-
fer case.
8. Disconnect transfer case shift motor and mode
sensor wire connectors (3).
9. Disconnect transfer case vent hose.
10. Support transfer case with transmission jack.
11. Secure transfer case to jack with chains.
12. Remove nuts attaching transfer case (2) to transmission (1).
13. Pull transfer case and jack rearward to disengage transfer case.
14. Remove transfer case from under vehicle.
DISASSEMBLY
Position transfer case in a shallow drain pan. Remove drain plug and drain any remaining lubricant remaining in
case.
SHIFT MOTOR ASSEMBLY AND FRONT OUTPUT SHAFT SEAL
1. Remove the bolts (3) which hold the shift motor
and mode sensor assembly (2) to the transfer case
(1).

2. Remove the shift motor and mode sensor assem-
bly from the transfer case.
3. Remove the front propeller shaft seal boot (1)
retaining clamp (2).
4. Remove the front propeller shaft seal boot (1).
5. Remove the front output shaft seal slinger (1) by
bending (2) the slinger ears away from the transfer
case.

5. Install 4-5 rear case (1)-to front case (2) bolts (3) to
hold rear case in position. Tighten bolts snug but
not to specified torque at this time.
CAUTION: Verify that shift rail, and case alignment
dowels are seated before installing any bolts.
Case could be cracked if shaft rail or dowels are
misaligned.
6. Apply Loctite™ 242 to remainder of rear case-to-
front case bolt threads and install bolts. Tighten
bolts to 20-27 Nꞏm (15-24 ft. lbs.).
7. Install rear output bearing (2) snap-ring (3) to out-
put shaft (1).
SEAL BOOT AND SHIFT MOTOR ASSEMBLY
1. Install the front output shaft seal slinger with Installer 8840. Install the slinger onto the shaft until the tool contacts
the rear of the output shaft.
2. Install a new seal boot clamp onto the seal boot.
3. Install the seal boot and clamp onto the slinger hub and tighten the clampwith Crimp Tool C-4975-A.
4. Position the shift motor and mode sensor assembly onto the transfer case.
5. Install the bolts to hold the shift motor and mode sensor assembly to the transfer case. Tighten the bolts to 16-25
Nꞏm (12-18 ft. lbs.).

REAR EXTENSION
1. Install new seal in rear extension housing seal with
Installer D-163 and Universal Handle C-4171..
2. Apply bead of Mopar
Gasket Maker, or equivalent,
to mating surface of rear extension housing. Keep
sealer bead width to maximum of 3/16 inch. Do not
use excessive amount of sealer as excess could
be displaced into output bearing.
3. Align and install rear extension (1) on the transfer
case (2).
4. Apply Mopar
Silicone Sealer to threads of rear
extension housing bolts. Then install and tighten
bolts to 16-24 Nꞏm (12-18 ft. lbs.) torque.
INSTALLATION
1. Mount transfer case on a transmission jack.
2. Secure transfer case to jack with chains.
3. Position transfer case under vehicle.
4. Align transfer case and transmission shafts and install transfer case onto the transmission.
5. Install and tighten transfer case attaching nuts to 27-34 Nꞏm (20-25 ft.lbs.) torque.
6. Connect the vent hose.
7. Connect the shift motor and mode sensor wiring connectors. Secure wire harness to clips on transfer case.
8. Align and connect the propeller shafts. (Refer to 3 - DIFFERENTIAL & DRIVELINE/PROPELLER SHAFT/FRONT
PROPELLER SHAFT - INSTALLATION) (Refer to 3 - DIFFERENTIAL & DRIVELINE/PROPELLER SHAFT/REAR
PROPELLER SHAFT - INSTALLATION)
9. Fill transfer case with correct fluid. (Refer to 21 - TRANSMISSION/TRANSFER CASE/FLUID - STANDARD PRO-
CEDURE)
10. Install skid plate, if equipped.
11. Remove transmission jack and support stand.
12. Lower vehicle and verify transfer case shift operation.
SPECIFICATIONS
TRANSFER CASE - NV243
TORQUE SPECIFICATIONS
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Plug, Detent 16-24 12-18 -
Plug, Drain/Fill 20-34 15-25 -
Bolt, Extension Housing 16-24 12-18 -
Bolt, Case Half 20-27 15-24 -
Screw, Oil Pump 12-16 8-12 -
Nuts, Mounting 30-41 20-30 -
Bolts, Shift Motor and
Mode Sensor Assembly16-24 12-18 -

SENSOR-MODE
DESCRIPTION
The transfer case mode sensor (1) is an electronic
device whose output can be interpreted to indicate the
shift motor shaft’s rotary position. The sensor consists
of a magnetic ring and four Hall Effect Transistors to
create a 4 channel digital device (non-contacting)
whose output converts the motor shaft position into a
coded signal. The TCCM must supply 5VDC (+/- 0.5v)
to the sensor and monitor the shift motor position. The
four channels are denoted A, B, C, and D. The sensor
is mechanically linked to the shaft of the cam which
causes the transfer case shifting. The mode sensor
draws less than 53 mA.
OPERATION
During normal vehicle operation, the Transfer Case Control Module (TCCM)monitors the mode sensor outputs at
least every 250 (+/-50) milliseconds when the shift motor is stationary and 400 microseconds when the shift motor
is active. A mode sensor signal between 3.8 Volts and 0.8 Volts is considered to be undefined.
Refer to SECTOR ANGLES vs. TRANSFER CASE POSITION for the relative angles of the transfer case shift sector
versus the interpreted transfer case gear operating mode. Refer to MODE SENSOR CHANNEL STATES for the
sensor codes returned to the TCCM for each transfer case mode sensor position. The various between gears posi-
tions can also be referred as the transfer case’s coarse position. These coarse positions come into play during shift
attempts.
SECTOR ANGLES vs. TRANSFER CASE POSITION
Shaft Angle (Degrees) Transfer Case Position
+40 4LO
+20 N
0 2WD/AWD
-20 4HI
MODE SENSOR CHANNEL STATES
Transfer Case
Angle (degrees)Sensor Channel A Sensor Channel B Sensor Channel C Sensor Channel D
Between Gears H H L H
+40 (4LO) H H L L
Between Gears H H L H
Between Gears H L L H
+20 (NEUTRAL) H L L L
Between Gears H L L H
Between Gears H L H H

Transfer Case
Angle (degrees)Sensor Channel A Sensor Channel B Sensor Channel C Sensor Channel D
0 (2WD/AWD) H L H L
Between Gears H L H H
Between Gears L L H H
-20 (4HI) L L H L
Between Gears L L H H
Between Gears L H H H

SWITCH-SELECTOR
DESCRIPTION
The selector switch assembly is mounted in the left
side of the vehicle’s Instrument Panel (IP) and con-
sists of a rotary knob connected to a resistive network
for the mode and range shift selections. Also located
in this assembly is a recessed, normally open momen-
tary switch for making shifts into and out of transfer
case NEUTRAL. A pen, or similar instrument, is used
to make a NEUTRAL shift selection, thus reducing the
likelihood of an inadvertent shift request.
The selector switch also contains four light emitting
diode’s (LED’s) to indicate the transfer case position
and whether a shift is in progress.
OPERATION
As the position of the selector switchvaries, the resistance between the Mode Sensor supply voltage pin and the
Mode Sensor output will vary. Hardware, software, and calibrations within the Transfer Case Control Module
(TCCM) are provided that interpret the selector switch resistance as giveninthetablebelow:SELECTORSWITCH
INTERPRETATION
SELECTOR SWITCH INTERPRETATION
Step Resistance Range (ohms) Required Interpretation
A <200 Shorted
B 400-700 NEUTRAL
C 1050-1450 4LO
D 1850-2300 4HI
E 3050-5950 2WD (Default)
F 9.5-12.5K In between positions
G>15.5KOpen
For resistances between the ranges B-E shown for each valid position (T-Case NEUTRAL, 4LO, 4HI, 2WD), the
TCCM may interpret the resistance as:
either of the neighboring valid positions.
as an invalid fault position.
For resistances between the ranges E and F shown for 2WD and in-between positions, the TCCM may interpret the
resistance as:
the 2WD position.
an invalid fault position.
a valid in-between position.
For resistances between the ranges F and G shown for in-between positions and fault condition (open), the TCCM
may interpret the resistance as:
a valid in-between position.
an invalid fault position.

MOTOR-SHIFT
DESCRIPTION
The shift motor (1) consists of a permanent magnet
D.C. motor with gear reduction to convert a high
speed-low torque device into a low speed-high torque
device. The output of the device is coupled to a shaft
which internally moves the mode and range forks that
change the transfer case operating ranges. The motor
is rated at 25 amps maximum at (23° C (72° F) with
10 volts at the motor leads.
OPERATION
The transfer case shift motor responds to the Transfer Case Control Module(TCCM) commands to move the trans-
fer case shift sector bi-directionally, as required, to obtain the transfer case operating mode indicated by the instru-
ment panel mounted selector switch.
REMOVAL
NOTE: New shift motor assemblies are shipped in the 2WD/AWD position. If a new shift motor assembly will
be installed, it will be necessary to shift the transfer case to the 2WD/AWDposition prior to motor removal.
1. Raise the vehicle on a suitable hoist.
2. Disengage the wiring connectors from the shift motor and mode sensor.
3. Remove the bolts holding the shift motor and mode sensor assembly onto the transfer case.
4. Separate the shift motor and mode sensor assembly from the transfer case.
INSTALLATION
1. Verify that the shift sector o-ring is clean and properly positioned over the shift sector and against the transfer
case.
NOTE: Verify that the shift motor position and sector shaft orientation are aligned. It may be necessary to
manually shift the transfer case if the shift motor and sector shaft are notaligned.
2. Position the shift motor and mode sensor assembly onto the transfer case.
3. Install the bolts to hold the assembly onto the transfer case. Tighten the bolts to 16-24 Nꞏm (12-18 ft.lbs.).
CAUTION: If the original shift motor and mode sensor assembly bolts are reused, be sure to use Mopar
Lock & Seal or Loctite™ 242 to replenish the lock patch material originallyfound on the bolts
4. Engage the wiring connectors to the shift motor and mode sensor.
5. Refill the transfer case as necessary.

ASSEMBLY-SHIFT MOTOR/MODE SENSOR
DESCRIPTION
The shift motor (1) consists of a permanent magnet
D.C. motor with gear reduction to convert a high
speed-low torque device into a low speed-high torque
device. The output of the device is coupled to a shaft
which internally moves the mode and range forks that
change the transfer case operating ranges. The motor
is rated at 25 amps maximum at (23° C (72° F) with
10 volts at the motor leads.
OPERATION
The transfer case shift motor responds to the Transfer Case Control Module(TCCM) commands to move the trans-
fer case shift sector bi-directionally, as required, to obtain the transfer case operating mode indicated by the instru-
ment panel mounted selector switch.