key DODGE RAM 2002 Service Manual Online

COLUMN
TABLE OF CONTENTS
page page
COLUMN
DESCRIPTION..........................6
OPERATION
SERVICE PRECAUTIONS................6
REMOVAL.............................6
INSTALLATION..........................8
SPECIFICATIONS
TORQUE CHART......................9
KEY-IN IGNITION SWITCH
DESCRIPTION..........................9
DIAGNOSIS AND TESTING - IGNITION
SWITCH AND KEY LOCK CYLINDER.......9
LOCK CYLINDER
REMOVAL.............................10INSTALLATION.........................10
IGNITION SWITCH
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - IGNITION
SWITCH.............................11
REMOVAL.............................12
INSTALLATION.........................12
GEAR SHIFT LEVER
REMOVAL.............................14
INSTALLATION.........................15
STEERING WHEEL
REMOVAL.............................15
INSTALLATION.........................15
COLUMN
DESCRIPTION
The tilt and standard column (Fig. 1) has been
designed to be serviced as an assembly; less wiring,
switches, shrouds, steering wheel, etc. Most steering
column components can be serviced without remov-
ing the steering column from the vehicle.
OPERATION
SERVICE PRECAUTIONS
Safety goggles should be worn at all times when
working on steering columns.
To service the steering wheel, switches or the air-
bag, refer to the WARNINGS and CAUTIONS below.
WARNING: THE AIRBAG SYSTEM IS A SENSITIVE,
COMPLEX ELECTRO-MECHANICAL UNIT. BEFORE
ATTEMPTING TO DIAGNOSE, REMOVE OR INSTALL
THE AIRBAG SYSTEM COMPONENTS YOU MUST
FIRST DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE. THEN WAIT TWO
MINUTES FOR THE SYSTEM CAPACITOR TO DIS-
CHARGE. FAILURE TO DO SO COULD RESULT IN
ACCIDENTAL DEPLOYMENT OF THE AIRBAG AND
POSSIBLE PERSONAL INJURY. THE FASTENERS,
SCREWS, AND BOLTS, ORIGINALLY USED FOR
THE AIRBAG COMPONENTS, HAVE SPECIAL COAT-INGS AND ARE SPECIFICALLY DESIGNED FOR THE
AIRBAG SYSTEM. THEY MUST NEVER BE
REPLACED WITH ANY SUBSTITUTES. ANYTIME A
NEW FASTENER IS NEEDED, REPLACE WITH THE
CORRECT FASTENERS PROVIDED IN THE SERVICE
PACKAGE OR FASTENERS LISTED IN THE PARTS
BOOKS.
CAUTION: Do not hammer on steering column shaft
or shift tube. This may cause the shaft/shift tube to
collapse or damage the bearing.
CAUTION: Do not attempt to remove the pivot pins
to disassemble the tilting mechanism. Do not
remove shaft lock plate, plate retainer, park lock
link or slider. This will damage the column (Fig. 2)
and (Fig. 3).
REMOVAL
(1) Position the front wheels straight ahead.
(2) Disconnect the negative (ground) cable from
the battery.
(3) Remove the airbag, (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - REMOVAL).
(4) Remove the steering wheel with an appropriate
puller,(Refer to 19 - STEERING/COLUMN/STEER-
ING WHEEL - REMOVAL).
19 - 6 COLUMNBR/BE

(8) Remove the PRNDL cable on column shift vehi-
cles. Put the shift lever inParkposition. Pull the
cable and twist to remove from the position arm.
Push the tab up on bottom of the cable retainer, then
squeeze sides to remove retainer from the column
(Fig. 5).
(9) Remove the tilt lever (if equipped) from the col-
umn.
(10) Remove the upper and lower lock housing
shroud and remove the lower fixed shroud.
(11) Remove the turn signal multi-function switch
connector with a 7mm socket (Fig. 6).(12) Loosen the upper Support Bracket nuts to
allow some slack. This will aid in removal of the
upper fixed shroud.
(13) Remove the electrical connections from Key-in
light, Ignition Switch, Horn, Overdrive Switch and
Clock Spring (Speed Control) (Fig. 7).
(14) Remove the wiring harness from the column
by prying out the plastic retainer buttons.
(15) Remove the toe plate fasteners.
(16) Remove the column from vehicle.
(17) Remove the Ignition and Multi-Function
Switch, then remove the Clock Spring and tape the
Clock Spring to prevent it from turning, (Refer to 8 -
ELECTRICAL/RESTRAINTS/CLOCKSPRING -
REMOVAL).
INSTALLATION
(1) Install the clock spring and switches, (Refer to
8 - ELECTRICAL/RESTRAINTS/CLOCKSPRING -
INSTALLATION).
NOTE: Turn the Ignition Switch to the on position
and verify the gear shifter moves. If the shifter does
not move ensure the Ignition Switch is installed
properly.
(2) Column shift vehicles, install a new grommet.
Use multi-purpose lubricant, or equivalent, to aid
installation of the grommet.
NOTE: A new grommet should be used when ever
the rod is disconnected from the lever.
Fig. 5 PRNDL Drive
1 - PRNDL LEVER
2 - THUMB SCREW
3 - CABLE RETAINER
4 - PRNDL CABLE
Fig. 6 Multi-function Switch
1 - STEERING COLUMN ASSY.
2 - MULTI-FUNCTION SWITCH CONNECTOR
3 - TURN SIGNAL SWITCH AND LEVER
Fig. 7 Steering Column Wiring
1 - KEY-IN SWITCH & HALO LIGHT
2 - MULTI-FUNCTION SWITCH
3 - TURN SIGNAL SWITCH & LEVER
4 - IGNITION SWITCH
5 - SPEED CONTROL
19 - 8 COLUMNBR/BE
COLUMN (Continued)

(3) Remove the shipping lock pin if necessary.
(4) Install the column through the floor pan.
(5) Position the column bracket breakaway cap-
sules on the mounting studs. Install, butloose
assemblethe two upper bracket nuts.
(6) With the front wheels in the straight-ahead
position. Align steering column shaft to the coupler.
Install anewpinch bolt and tighten to 49 N´m (36
ft. lbs.).
(7) Clip the wiring harness on the steering column.
Connect the multi- function switch wiring and
tighten with 7mm socket.
(8) Install the upper fixed shroud.
(9) Be sure both breakaway capsules are fully
seated in the slots in the column support bracket.
Pull the column rearward then tighten upper bracket
nuts to 12 N´m (105 in. lbs.).
(10) Tighten the toe plate to floor pan attaching
nuts to 22.5 N´m (200 in. lbs.).
(11) Install the wiring connections to the column.
Install the lower fixed shroud.
(12) Column shift vehicles, install the PRNDL
driver cable. Place shifter in Park position. If indica-tor needs adjusting, turn thumb screw on cable
retainer to adjust cable.
(13) Install the lock housing shrouds. Install the
tilt lever (if equipped).
(14) Install the knee blocker and steering column
opening cover, (Refer to 23 - BODY/INSTRUMENT
PANEL/STEERING COLUMN OPENING COVER -
INSTALLATION).
(15) Install steering wheel and tighten nut to 61
N´m (45 ft. lbs.), (Refer to 19 - STEERING/COL-
UMN/STEERING WHEEL - INSTALLATION).
(16) Install the airbag, (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - INSTALLATION).
(17) Column shift vehicles, connect the shift link
rod to the transmission shift lever. Use multi-purpose
lubricant, or an equivalent product, to aid the instal-
lation.
(18) Install the battery ground (negative) cable.
(19) Verify operation of the automatic transmission
shift linkage and adjust as necessary, (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
44RE/GEAR SHIFT CABLE - ADJUSTMENTS).
SPECIFICATIONS
TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Steering Wheel
Nut61 45 Ð
Steering Coupler
Bolt49 36 Ð
Steering Column
Upper Bracket12 Ð 105
Steering Column
Toe Plate23 Ð 200
KEY-IN IGNITION SWITCH
DESCRIPTION
The key-in ignition switch is integral to the igni-
tion switch, which is mounted on the left side of the
steering column. It closes a path to ground for the
Central Timer Module (CTM) when the ignition key
is inserted in the ignition lock cylinder and the
driver door ajar switch is closed (driver door is open).
The key-in ignition switch opens the ground path
when the key is removed from the ignition lock cyl-
inder. The ground path is also opened when the
driver door ajar switch is open (driver door is closed).The key-in ignition switch cannot be repaired and,
if faulty or damaged, the entire ignition switch must
be replaced, (Refer to 19 - STEERING/COLUMN/IG-
NITION SWITCH - REMOVAL).
DIAGNOSIS AND TESTING - IGNITION SWITCH
AND KEY LOCK CYLINDER
ELECTRICAL DIAGNOSIS
For ignition switch electrical schematics, refer to
Ignition Switch in the appropriate section of Electri-
cal Wiring Diagrams.
BR/BECOLUMN 19 - 9
COLUMN (Continued)

MECHANICAL DIAGNOSIS (KEY DIFFICULT TO
ROTATE)
Vehicles equipped with an automatic trans-
mission and a floor mounted shifter:a cable is
used to connect the interlock device in the steering
column assembly, to the transmission floor shift
lever. This interlock device is used to lock the trans-
mission shifter in the PARK position when the key
lock cylinder is rotated to the LOCKED or ACCES-
SORY position. The interlock device within the steer-
ing column is not serviceable. If repair is necessary,
the steering column assembly must be replaced.
(Refer to 19 - STEERING/COLUMN - REMOVAL).
If the ignition key is difficult to rotate to or from
the LOCK or ACCESSORY position, it may not be
the fault of the key cylinder or the steering column
components. The brake transmission shift interlock
cable may be out of adjustment. Refer to Brake
Transmission Shift Interlock Cable Adjustment in
Transmissions for adjustment procedures.
Vehicles equipped with an automatic trans-
mission and a steering column mounted shifter:
an interlock device is located within the steering col-
umn. This interlock device is used to lock the trans-
mission shifter in the PARK position when the key
lock cylinder is in the LOCKED or ACCESSORY
position. If it is difficult to rotate the key to or from
the LOCK or ACCESSORY position, the interlock
device within the steering column may be defective.
This device is not serviceable. If repair is necessary,
the steering column assembly must be replaced.
(Refer to 19 - STEERING/COLUMN - REMOVAL).
Vehicles equipped with a manual transmis-
sion and a floor mounted shifter:on certain mod-
els, a lever is located on the steering column behind
the ignition key lock cylinder. The lever must be
manually operated to allow rotation of the ignition
key lock cylinder to the LOCK or ACCESSORY posi-
tion. If it is difficult to rotate the key to the LOCK or
ACCESSORY position, the lever mechanism may be
defective. This mechanism is not serviceable. If
repair is necessary, the steering column assembly
must be replaced. (Refer to 19 - STEERING/COL-
UMN - REMOVAL).
On other models, the ignition key cylinder must be
depressed to allow it to be rotated into the LOCK or
ACCESSORY position. If it is difficult to rotate the
key to the LOCK or ACCESSORY position, the lock
mechanism within the steering column may be defec-
tive. This mechanism is not serviceable. If repair is
necessary, the steering column assembly must be
replaced. (Refer to 19 - STEERING/COLUMN -
REMOVAL).
LOCK CYLINDER
REMOVAL
The ignition key must be in the key cylinder for
cylinder removal.
(1) Disconnect negative cable from battery.
(2) If equipped with tilt column, remove tilt lever
by turning it counterclockwise.
(3) Remove upper and lower covers (shrouds) from
steering column (Fig. 8).
(4) If equipped with automatic transmission, place
shifter in PARK position.
(5) A retaining pin (Fig. 9) is located at side of key
cylinder assembly.
(a) Rotate key to RUN position.
(b) Press in on retaining pin while pulling key
cylinder from ignition switch.
INSTALLATION
The ignition key must be in the key cylinder and
turned clockwise to the RUN position for cylinder
installation.
Fig. 8 Shroud Removal/InstallationÐTypical
1 - NUT
2 - STEERING WHEEL
3 - TILT LEVER
4 - UPPER SHROUD
5 - PANEL BRACKET
6 - SPACER
7 - NUT
8 - LOWER SHROUD
9 - CLOCK SPRING
19 - 10 COLUMNBR/BE
KEY-IN IGNITION SWITCH (Continued)

(1) Install the lock cylinder into the housing using
care to align the end of the lock cylinder with the
ignition switch.
(2) Push the lock cylinder in until it clicks.
IGNITION SWITCH
DESCRIPTION
The electrical ignition switch is located on the
steering column. It is used as the main on/off switch-
ing device for most electrical components. The
mechanical key lock cylinder is used to engage/disen-
gage the electrical ignition switch.
OPERATION
Vehicles equipped with an automatic trans-
mission and a steering column mounted shifter:
an interlock device is located within the steering col-
umn. This interlock device is used to lock the trans-
mission shifter in the PARK position when the key
lock cylinder is in the LOCKED or ACCESSORY
position. If it is difficult to rotate the key to or from
the LOCK or ACCESSORY position, the interlock
device within the steering column may be defective.
This device is not serviceable. If repair is necessary,
the steering column assembly must be replaced.
(Refer to 19 - STEERING/COLUMN - REMOVAL).
Vehicles equipped with a manual transmis-
sion and a floor mounted shifter:on certain mod-
els, a lever is located on the steering column behind
the ignition key lock cylinder. The lever must be
manually operated to allow rotation of the ignitionkey lock cylinder to the LOCK or ACCESSORY posi-
tion. If it is difficult to rotate the key to the LOCK or
ACCESSORY position, the lever mechanism may be
defective. This mechanism is not serviceable. If
repair is necessary, the steering column assembly
must be replaced. (Refer to 19 - STEERING/COL-
UMN - REMOVAL).
On other models, the ignition key cylinder must be
depressed to allow it to be rotated into the LOCK or
ACCESSORY position. If it is difficult to rotate the
key to the LOCK or ACCESSORY position, the lock
mechanism within the steering column may be defec-
tive. This mechanism is not serviceable. If repair is
necessary, the steering column assembly must be
replaced. (Refer to 19 - STEERING/COLUMN -
REMOVAL).
DIAGNOSIS AND TESTING - IGNITION SWITCH
TEST AND REPAIR
If the key removal effort is excessive on a vehicle
with a automatic transmission first adjust the shift
linkage, (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 42RE/GEAR SHIFT CABLE -
ADJUSTMENTS).
If the ignition switch effort is excessive remove the
ignition key cylinder from the steering column. (Refer
to 19 - STEERING/COLUMN/LOCK CYLINDER
HOUSING - INSTALLATION). Check the turning
effort of the key cylinder. If the ignition key cylinder
effort is excessive replace the key cylinder. If the
ignition key cylinder operates properly look for the
following conditions.
(1) Look for rough areas or flash in the casting
and if found remove with a file (Fig. 10).
(2) Grease the lock plate actuator, lock plate, slider
and locking link.
Fig. 9 Retaining Pin
1 - IGNITION SWITCH
2 - KEY/KEY CYLINDER (RUN POSITION)
3 - RETAINING PIN
Fig. 10 Steering Column Flash Removal
1 - FILE THIS AREA TO REMOVE FLASHING AND PROVIDE
CLEARANCE TO ELIMINATE BINDING
2 - PARK LOCK SLIDER
3 - CAUTION: NEVER REMOVE SHAFT LOCK PLATE
BR/BECOLUMN 19 - 11
LOCK CYLINDER (Continued)

REMOVAL
(1) Remove the key lock cylinder.
(2) Remove the three ignition mounting screws
(Fig. 11).
(3) Gently pull the switch away from the column.
Disconnect the electrical connector (Fig. 12).
(4) Disconnect the halo lamp wiring connector
(Fig. 12).
INSTALLATION
(1) Rotate the flag on the rear of the ignition
switch to the RUN position (Fig. 13). This step must
be done to allow the tang (Fig. 14) on the key cylin-
der to fit into the slots (Fig. 11)within the ignition
switch.
(2) With the key into the key lock cylinder, rotate
the key clockwise until the retaining pin can be
depressed (Fig. 14) or (Fig. 15).
(3) Install the key cylinder into the ignition switch
by aligning the retaining pin slot. Push the key cyl-
inder into the switch until the retaining pin engages.
After the pin engages, rotate the key to the OFF or
LOCK position.
(4) Check for proper retention of the key cylinder
by attempting to pull the cylinder from the switch.
(5) Automatic Transmission Only: Before attaching
the ignition switch to the steering column, the trans-
mission shifter must be in the PARK position. The
park lock dowel pin on the rear of the ignition switch
(Fig. 16) must also be properly indexed into the park
lock linkage (Fig. 17) before installing the switch.
(6) The flag at the rear of the ignition switch
must be properly indexed into the steering column
before installing the switch. This flag is used to oper-
ate the steering wheel lock lever in the steering col-
umn (Fig. 18). This lever allows the steering wheel
position to be locked when the key is in the LOCK
position.
(7) Place the ignition switch in the LOCK position.
The switch is in the LOCK position when the column
lock flag is parallel to the ignition switch terminals
(Fig. 16).
Fig. 11 SWITCH MOUNTING SCREWS
1 - IGNITION SWITCH
2 - SLOTS NOT ALIGNED
3 - SLOTS ALIGNED
4 - IGNITION SWITCH MOUNTING SCREWS
Fig. 12 IGNITION SWITCH AND HALO
CONNECTORS
1 - KEY-IN SWITCH & HALO LIGHT
2 - MULTI-FUNCTION SWITCH
3 - TURN SIGNAL SWITCH & LEVER
4 - IGNITION SWITCH
5 - SPEED CONTROL
Fig. 13 FLAG IN RUN POSITION
1 - REAR OF IGNITION SWITCH
2 - PARK LOCK DOWEL PIN (RUN POSITION)
3 - FLAG (RUN POSITION)
19 - 12 COLUMNBR/BE
IGNITION SWITCH (Continued)

(8) Automatic Transmissions Only: Apply a light
coating of grease to the park lock dowel pin and park
lock slider linkage. Before installing the switch, push
the park lock slider linkage (Fig. 17)forward until it
bottoms. Do a final positioning by pulling it rear-
wards about one-quarter inch.
(9) Apply a light coating of grease to both the col-
umn lock flag and shaft at the end of the flag.
(10) Place the ignition switch into the openings on
the steering column(a) Automatic Transmissions Only: Be sure the
park lock dowel pin on the rear of the ignition
switch enters the slot in the park lock slider link-
age (Fig. 17).
(b) Be sure the flag on the rear of the switch is
positioned above the steering wheel lock lever (Fig.
18).
(c) Align the dowel pins on the rear of the switch
into the holes on the side of the steering column.
(d) Install the three ignition mounting screws.
Tighten the screws to 2 N´m (17 in. lbs.).
Fig. 14 KEY CYLINDER --- REAR VIEW
1 - IGNITION KEY LOCK CYLINDER
2 - PUSH PIN
3 - RETAINING PIN SLOT
4 - RETAINING PIN
5 - DRIVER
Fig. 15 INSTALLING KEY CYLINDER INTO SWITCH
1 - IGNITION SWITCH
2 - DRIVER
3 - IGNITION KEY LOCK CYLINDER
4 - RETAINING PIN
5 - RETAINING PIN SLOT
Fig. 16 IGNITION SWITCH VIEW FROM COLUMN
1 - REAR OF IGNITION SWITCH
2 - PARK LOCK DOWEL PIN (LOCK POSITION)
3 - FLAG (LOCK POSITION)
Fig. 17 PARK LOCK LINKAGE -- AUTOMATIC
TRANSMISSION -- TYPICAL
1 - DOWEL LOCATING HOLES (2)
2 - PARK LOCK SLIDER LINKAGE
3 - IGNITION SWITCH MOUNTING PAD
4 - STEERING COLUMN
5 - SLOT
BR/BECOLUMN 19 - 13
IGNITION SWITCH (Continued)

(e) After installing the ignition switch rotate the
ignition key from the LOCK to the ON position.
Verify that the park lock slider moves in the slider
slot, allowing the gear shift lever to be moved out
of PARK (automatic transmissions only). If the
slider does not move , and the gear shift lever is
locked in PARK, the ignition switch park lock
dowel pin, on the rear of the ignition switch, is not
properly installed in the slot of the park lock slider
linkage. Remove the ignition switch and reinstall.
(11) Connect the electrical connectors for the igni-
tion switch and halo lamp.
(12) Install the steering column shrouds. Tighten
the screws to 2 N´m (17 in. lbs.).
(13) Install the tilt column lever. (if equipped).
(14) Connect the battery.
(15) Automatic Transmissions Only: The shifter
should lock in the PARK position when the key is in
the LOCK position (if equipped with a shift lock
device). The shifter should unlock when the key is
rotated to the ON position.
(16) Check for proper operation of the ignition
switch in ACCESSARY, LOCK, OFF, ON, RUN and
start positions.
(17) The steering wheel should lock when the key
is in the LOCK position. Rotate the steering wheel at
least 180É to verify. The steering wheel should unlock
when the key is rotated to the ON position.GEAR SHIFT LEVER
REMOVAL
(1) Remove the tilt lever.
(2) Remove the upper and lower shrouds.
(3) Remove the steering column opening cover
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - REMOVAL).
(4) Remove the steering column mounting nuts.
(5) Lower the steering column to remove the sec-
ondary shrouds.
(6) Raise the steering column back on the mount-
ing bolts and finger tighten the nuts.
(7) Disconnect over drive switch wiring.
(8) Using a drift of the appropriate size drive the
knurled pin out of the steering column and gear shift
lever. Remove the gear shift lever from the steering
column assembly.
CAUTION: The pin can only be removed from the
direction shown (Fig. 19).
Fig. 18 STEERING WHEEL LOCK LEVER
1 - STEERING COLUMN
2 - STEERING WHEEL LOCK LEVER
3 - LOCATER (SHAFT AT END OF FLAG)
Fig. 19 Gear Shift Lever Removal
1 - IGNITION SWITCH
2 - KNURLED PIN
3 - GEARSHIFT LEVER
4 - SOCKET
5 - DRIFT
6 - HAMMER
19 - 14 COLUMNBR/BE
IGNITION SWITCH (Continued)

Note that the rear clutch is applied in all forward
ranges (D, 2, 1). The transmission overrunning clutch
is applied in first gear (D, 2 and 1 ranges) only. The
rear band is applied in 1 and R range only.
Note that the overdrive clutch is applied only in
fourth gear and the overdrive direct clutch and over-
running clutch are applied in all ranges except fourth
gear.
For example: If slippage occurs in first gear in D
and 2 range but not in 1 range, the transmission
overrunning clutch is faulty. Similarly, if slippage
occurs in any two forward gears, the rear clutch is
slipping.
Applying the same method of analysis, note that
the front and rear clutches are applied simulta-
neously only in D range third and fourth gear. If the
transmission slips in third gear, either the front
clutch or the rear clutch is slipping.
If the transmission slips in fourth gear but not in
third gear, the overdrive clutch is slipping. By select-
ing another gear which does not use these clutches,
the slipping unit can be determined. For example, if
the transmission also slips in Reverse, the front
clutch is slipping. If the transmission does not slip in
Reverse, the rear clutch is slipping.
If slippage occurs during the 3-4 shift or only in
fourth gear, the overdrive clutch is slipping. Simi-
larly, if the direct clutch were to fail, the transmis-
sion would lose both reverse gear and overrun
braking in 2 position (manual second gear).
If the transmission will not shift to fourth gear, the
control switch, overdrive solenoid or related wiring
may also be the problem cause.
This process of elimination can be used to identify
a slipping unit and check operation. Proper use of
the Clutch and Band Application Chart is the key.
Although road test analysis will help determine the
slipping unit, the actual cause of a malfunction usu-
ally cannot be determined until hydraulic and air
pressure tests are performed. Practically any condi-
tion can be caused by leaking hydraulic circuits or
sticking valves.
Unless a malfunction is obvious, such as no drive
in D range first gear, do not disassemble the trans-
mission. Perform the hydraulic and air pressure tests
to help determine the probable cause.
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST
Hydraulic test pressures range from a low of one
psi (6.895 kPa) governor pressure, to 300 psi (2068
kPa) at the rear servo pressure port in reverse.
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3292 has a 100 psi range
and is used at the accumulator, governor, and front
servo ports. Test Gauge C-3293-SP has a 300 psirange and is used at the rear servo and overdrive
ports where pressures exceed 100 psi.
Pressure Test Port Locations
Test ports are located at both sides of the transmis-
sion case (Fig. 9).
Line pressure is checked at the accumulator port
on the right side of the case. The front servo pressure
port is at the right side of the case just behind the
filler tube opening.
The rear servo and governor pressure ports are at
the right rear of the transmission case. The overdrive
clutch pressure port is at the left rear of the case.
Test One - Transmission In Manual Low
This test checks pump output, pressure regulation,
and condition of the rear clutch and servo circuit.
Both test gauges are required for this test.
(1) Connect tachometer to engine. Position tachom-
eter so it can be observed from driver seat if helper
will be operating engine. Raise vehicle on hoist that
will allow rear wheels to rotate freely.
Fig. 9 Pressure Test Port Locations
1 - REAR SERVO TEST PORT
2 - GOVERNOR TEST PORT
3 - ACCUMULATOR TEST PORT
4 - FRONT SERVO TEST PORT
5 - OVERDRIVE CLUTCH TEST PORT
21 - 98 AUTOMATIC TRANSMISSION - 46REBR/BE
AUTOMATIC TRANSMISSION - 46RE (Continued)

GOVERNOR PRESSURE CURVES
There are four governor pressure curves pro-
grammed into the transmission control module. The
different curves allow the control module to adjust
governor pressure for varying conditions. One curve
is used for operation when fluid temperature is at, or
below, ±1ÉC (30ÉF). A second curve is used when fluid
temperature is at, or above, 10ÉC (50ÉF) during nor-
mal city or highway driving. A third curve is used
during wide-open throttle operation. The fourth curve
is used when driving with the transfer case in low
range.
OPERATION
Compensation is required for performance varia-
tions of two of the input devices. Though the slope of
the transfer functions is tightly controlled, offset may
vary due to various environmental factors or manu-
facturing tolerances.
The pressure transducer is affected by barometric
pressure as well as temperature. Calibration of the
zero pressure offset is required to compensate for
shifting output due to these factors.
Normal calibration will be performed when sump
temperature is above 50 degrees F, or in the absence
of sump temperature data, after the first 10 minutes
of vehicle operation. Calibration of the pressure
transducer offset occurs each time the output shaft
speed falls below 200 RPM. Calibration shall be
repeated each 3 seconds the output shaft speed is
below 200 RPM. A 0.5 second pulse of 95% duty cycle
is applied to the governor pressure solenoid valve
and the transducer output is read during this pulse.
Averaging of the transducer signal is necessary to
reject electrical noise.
Under cold conditions (below 50 degrees F sump),
the governor pressure solenoid valve response may
be too slow to guarantee 0 psi during the 0.5 second
calibration pulse. Calibration pulses are continued
during this period, however the transducer output
valves are discarded. Transducer offset must be read
at key-on, under conditions which promote a stable
reading. This value is retained and becomes the off-
set during the9cold9period of operation.
GOVERNOR PRESSURE SOLENOID VALVE
The inlet side of the solenoid valve is exposed to
normal transmission line pressure. The outlet side of
the valve leads to the valve body governor circuit.
The solenoid valve regulates line pressure to pro-
duce governor pressure. The average current sup-
plied to the solenoid controls governor pressure. One
amp current produces zero kPa/psi governor pres-
sure. Zero amps sets the maximum governor pres-
sure.The powertrain control module (PCM) turns on the
trans control relay which supplies electrical power to
the solenoid valve. Operating voltage is 12 volts
(DC). The PCM controls the ground side of the sole-
noid using the governor pressure solenoid control cir-
cuit.
GOVERNOR PRESSURE SENSOR
The sensor output signal provides the necessary
feedback to the PCM. This feedback is needed to ade-
quately control governor pressure.
GOVERNOR BODY AND TRANSFER PLATE
The transfer plate channels line pressure to the
solenoid valve through the governor body. It also
channels governor pressure from the solenoid valve
to the governor circuit. It is the solenoid valve that
develops the necessary governor pressure.
GOVERNOR PRESSURE CURVES
LOW TRANSMISSION FLUID TEMPERATURE
When the transmission fluid is cold the conven-
tional governor can delay shifts, resulting in higher
than normal shift speeds and harsh shifts. The elec-
tronically controlled low temperature governor pres-
sure curve is higher than normal to make the
transmission shift at normal speeds and sooner. The
PCM uses a temperature sensor in the transmission
oil sump to determine when low temperature gover-
nor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased
computing power of the PCM and through access to
data on engine operating conditions provided by the
PCM that were not available with the previous
stand-alone electronic module. This facilitated the
development of a load adaptive shift strategy - the
ability to alter the shift schedule in response to vehi-
cle load condition. One manifestation of this capabil-
ity is grade9hunting9prevention - the ability of the
transmission logic to delay an upshift on a grade if
the engine does not have sufficient power to main-
tain speed in the higher gear. The 3-2 downshift and
the potential for hunting between gears occurs with a
heavily loaded vehicle or on steep grades. When
hunting occurs, it is very objectionable because shifts
are frequent and accompanied by large changes in
noise and acceleration.
WIDE OPEN THROTTLE OPERATION
In wide-open throttle (WOT) mode, adaptive mem-
ory in the PCM assures that up-shifts occur at the
preprogrammed optimum speed. WOT operation is
determined from the throttle position sensor, which
is also a part of the emission control system. The ini-
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ELECTRONIC GOVERNOR (Continued)