PROPELLER SHAFT 3C-5
5. If difficult to remove, clamp the yoke side in a vise and tap
off the needle bearing, using a proper tool.
6. Disassemble the universal joint parts.
lAs axles move up and down, universal joints allow drive
angles to change without binding propeller shaft.
1 Grease Nipple
2 Flange Yoke
3 Spider4 Seal
5 Needle Roller Bearing
6 Snap Ring
4. Slightly tapping the yoke shoulder using a brass hammer,
remove the bearing. Remove the remaining bearings in the
same way.
POWER BOOSTER 4C-5
PEDAL STROKE INSPECTION
1. Start the engine and stop it after one or two minutes.
Depress the brake pedal several times.
If the pedal goes down furthest the first time, but gradually
rises after the second or third time, brake booster is normal.
If there is no change in pedal stroke, the brake booster is
abnormal.
2. Depress the brake pedal several times with engine stopped,
and depress the brake pedal and start the engine. If the
pedal goes down slightly, the booster is normal.
3. Depress the brake pedal with engine running, and stop it
with the pedal depressed. If there is no change in pedal
height during 30 sec., the booster is normal.
4F-6 ANTILOCK BRAKE SYSTEM
ABS,ABS/ABD
COMPONENT LOCATOR
1 ABS Hydraulic Unit
2 ABS/ABD Hydraulic Unit
3 Diagnosis Socket
4 Front Wheel Speed Sensor
5 Front Impulse Ring6 Rear Wheel Speed Sensor
7 Rear Impulse Ring
8 ABS Warning Indicator Light
9 TCS Indicator Light
1 0 ABS/ABD ECU
ANTILOCK BRAKE SYSTEM 4F-11
ABS, ABS/ABD 5.0
Initializing
1. Set the ignition switch n “ON” position.
2. Connect the No.1 terminal (Ground) and the No.13 (ABS)
from diagnosis socket located in E/G room by use of service
connector for 3 - 4 seconds and initialize the flash code.
Notice
Be careful not to connect over 5 seconds.
3. ABS indicator warning light continuously comes on until the
ignition switch is “OFF”.
Dignosis Table
1. When the system is normal
lOne pulse (normal code 01) indicates.
2. When the system is abnormal
lOne pulse (defect code) indicates.
Notice
Repeat the initializing procedure when checking the
defect code Defect code is indicated once for 1 sec (light
on : 0.75 sec, light off : 0.25 sec).
Removal the Defect Code
1. Repair the defect code and remove the memorized defect
code in the ECU.
2. Connect the No. 13 terminal (ABS) from diagnosis socket
and No. 1 terminal (ground) for over 5 seconds.
3. Set the ignition switch in the “OFF” position.
Notice
lDefect code will be memorized in ECU unless the defect
code is not removed.
lRepeat the initializing procedure and check the other
defects.
5A-20 AUTOMATIC TRANSMISSION
OPERATOR INTERFACES
There are three operator interfaces associated with the four speed transmission.
They are:
lThe gear select lever
lThe driving mode selector
lThe indicator light
These operator interfaces are described below.
GEAR SELECT LEVER OPERATION
The transmission uses a conventional selector lever. The selector lever can be moved from one position to another
within the staggered configuration of the selector lever gate to positively indicate the gear -selection as shown on
figure 2.1. For information about the gear selections available refer to table 2.1.
Figure 2.1 - Typical Gear Selector and Mode Switch
AUTOMATIC TRANSMISSION 5A-21
Downshift Type
RANGE ‘1’ (MANUAL ‘1’):
RANGE ‘2’ (MANUAL ‘2’):
RANGE ‘3’ (MANUAL ‘3’):
RANGE ‘D’ (DRIVE):
RANGE ‘N’ (NEUTRAL):
RANGE ‘R’ (REVERSE):
RANGE ‘P’ (PARK):Inhibited Above
First gear operation only with inhibited engagement as a function of vehicle
speed. Engine braking is applied with reduced throttle.
First and second gear operation with inhibited engagement of second gear, as
a function of vehicle speed. Engine braking is applied with reduced throttle.
First, second and third gear operation with an inhibited third gear engagement
at high vehicle speed. Refer to the vehicle owner’s manual.
Engine braking is applied with reduced throttle.
First, second, third and fourth gear operation. First to second (1-2), first to third
(1-3), second to third (2-3), second to fourth (2-4), third to fourth (3-4), fourth
to third (4-3), fourth to second (4-2), third to second (3-2), third to first (3-1)
and second to first (2-1), shifts are all available as a function of vehicle speed,
throttle position and the time rate of change of the throttle position (forced
downshift). Lockup clutch may be enabled in 3rd and 4th gears depending on
vehicle type. Refer to the owner’s manual.
Rear band applied only, with inhibited engagement as a function of vehicle
speed, engine speed and throttle position. The inhibitor switch allows the en-
gine to start.
Reverse gear operation, with inhibitor engagement as a function of vehicle
speed, engine speed and throttle position. The inhibitor switch enables reverse
lamp operation.
Rear band applied only, with inhibited engagement as a function of vehicle
speed, engine speed and throttle position. The transmission output shaft is
locked. The inhibitor switch allows the engine to start.
Table 2.1 - Gear Selections
DRIVING MODE SELECTOR
The driving mode selector consists of a mode selection switch and indicator light. The driving mode selector is
located on the centre console. See figure 2,1.
The schedules available to be selected vary with vehicle types. Typically the driver should have the option to select
between ‘NORMAL’ , ‘POWER’ or ‘WINTER’ modes.
When ‘NORMAL’ mode is selected upshifts will occur to maximise fuel economy and the indicator lights remain
extinguished. When ‘POWER’ mode is selected upshifts will occur to give maximum performance and the ‘POWER’
mode indicator light is switched on. When ‘WINTER’ mode is selected, starting at second gear is facilitated, the
‘WINTER’ mode indicator light is switched on and the ‘POWER’ mode indicator light is switched off.
Refer to the vehicle owner’s manual for specific modes for each vehicle type.
5A-24 AUTOMATIC TRANSMISSION
Transmission Control Unit(TCU)
The TCU is an in-vehicle micro-processor based transmission management system. It is usually mounted in the
vehicle cabin, under the instrument panel, under the seat, behind the side kick panels or under the floor in the
footwell on the passenger side. Different control units are supplied for different vehicle applications.
The TCU contains:
lProcessing logic circuits which include a central microcontroller and a back-up memory system.
lInput circuits.
lOutput circuits which control external devices such as the variable pressure solenoid (VPS), on/off solenoid
drivers, a diagnostics output and the driving mode indicator light.
The various items which make up the TCU are discussed below.
Processing Logic
Shift schedule and calibration information is stored in an erasable programmable read only memory (EEPROM).
Throttle input calibration constants and the diagnostics information are stored in electrically erasable programmable
read only memory (EEPROM) that retains the memory even when power to the TCU is disconnected.
In operation the software continuously monitors the input values and uses these, via the shift schedule, to determine
the required gear state, At the same time it monitors, via the solenoid outputs, the current gear state. Whenever the
input conditions change such that the required gear state is different to the current gear state, the TCU initiates a
gear shift to bring the two states back into line.
Once the TCU has determined the type of gear shift required the software accesses the shift logic, estimates the
engine torque output, adjusts the variable pressure solenoid ramp pressure then executes the shift.
The TCU continuously monitors every input and output circuit for short or open circuits and operating range. When
a failure or abnormal operation is detected the TCU records the condition code in the diagnostics memory and
implements a limp mode, The actual limp mode used depends upon the failure detected with the object to maintain
maximum driveability without damaging the transmission. In general input failures are handled by providing a default
value. Output failures, which are capable of damaging the transmission, result in full limp mode giving only third or
fourth gear and reverse. For further details of limp modes and memory retention refer to the Diagnostic Section.
The TCU is designed to operate at ambient temperatures between -40 and 85°C . It is also protected against
electrical noise and voltage spikes, however all the usual precautions should be observed, for example when arc
welding or jump starting.
TCU Inputs
To function correctly, the TCU requires engine speed, road speed, transmission sump temperature, throttle position
and gear position inputs to determine the variable pressure solenoid current ramp and on/off solenoid states. This
ensures the correct gear selection and shift feel for all driving conditions.
The inputs required by the TCU are as follows:
lEngine Speed
The engine speed signal is derived from the tachometer signal line, a dedicated sensor or a Controlled Area
Network (CAN).
lRoad Speed
4WD (Diesel) - The shaft speed signal is derived from the speedo sensor located on the transfer case. This signal
is transmitted directly to the TCU.
4WD (Gasoline) - The speedo sensor sends the shaft speed signal to the engine control module (ECM). The
information is then transferred to the TCU via the CAN.
lTransmission Sump Temperature
The transmission sump temperature sensor is a thermistor located in the solenoid wiring loom within the transmission.
This sensor is a typical NTC resistor with low temperatures producing a high resistance and high temperatures
5A-30 AUTOMATIC TRANSMISSION
Solenoid Valve Symbols (On/off Solenoids)
The solenoid symbol shown adjacent to each solenoid on the
hydraulic system schematics indicates the state of the oil flow
through the solenoid valve with the power On or 0ff. Refer to
figure 3.6 for the On/off operational details of NO solenoid
valves.
Normally Open (NO) Solenoid
POWER ON
Line 500 port is closed. The output port is open to exhaust at
the solenoid valve.
POWER OFF
The exhaust port is closed. The output port is open to line 500,Figure 3.6- Normally Open (NO) Symbols
Variable Pressure Solenoid Multiplexing System
Friction element shifting pressures are controlled by the variable pressure solenoid (VPS).
Line pressure is completely independent of shift pressure and is a function of throttle position, gear state and engine
speed.
S5 is a proportional or variable pressure solenoid that provides the signal pressure to the clutch and band regulator
valves thereby controlling shift pressures.
VPS pressure is multiplexed to the clutch regulator valve, the band regulator valve and the converter clutch regulator
valve during automatic gearshifts.
A variable pressure solenoid produces a hydraulic pressure inversely proportional to the current applied. During a
gearshift the TCU applies a progressively increasing or decreasing (ramped) current to the solenoid. Current applied
will vary between a minimum of 200 mA and a maximum of 1000 mA, Increasing current decreases output (55)
pressure. Decreasing current increases output (55) pressure.
Line 500 pressure, (approximately 440 to 560 kPa), is the reference pressure for the VPS, and the VPS output
pressure is always below line 500 pressure.
When the VPS is at standby, that is no gearshift is taking place, the VPS current is set to 200 mA giving maximum
output pressure.
Under steady state conditions the band and clutch regulator valve solenoids are switched off. This applies full Line
500 pressure to the plunger and because Line 500 pressure is always greater than S5 pressure it squeezes the S5
oil out between the regulator valve and the plunger. The friction elements are then fed oil pressure equal to Line 500
multiplied by the amplification ratio.
When a shift is initiated the required On/off solenoid is switched on cutting the supply of Line 500 to the plunger.
At the same time the VPS pressure is reduced to the ramp start value and assumes control of the regulator valve by
pushing the plunger away from the valve. The VPS then carries out the required pressure ramp and the timed shift is
completed by switching Off the On/off solenoid and returning the VPS to the standby pressure.
This system enables either the band or clutch or both to be electrically controlled for each gearshift.
Mode Indicator Light
Depending on the application, the mode indicator light may be used to indicate the mode that has been selected or
if an overheat condition exists. The mode indicator light is usually located on the instrument cluster.
Communication Systems
CAN
The controller area network (CAN) connects various control modules by using a twisted pair of wires, to share
common information. This results in a reduction of sensors and wiring. Typical applications include using the engine
controller to obtain the actual engine speed and throttle position, and adding these to the network. The ABS controller
(if fitted) can be used to obtain the road speed signal. This information is then available to the TCU without any
additional sensors.