sensor SSANGYONG MUSSO 1998 Workshop Repair Manual

4F-18 ANTILOCK BRAKE SYSTEM
ApplicationDefect CodeDescription
lCheck connection between connectors.
lCheck relevant wires for open or short.
(When connector is removed)
lCheck and replace the acceleration sensor.
lReplace the ECU.
lCheck voltage between ECU side ground (ABD:No.1,
ABS:No.15 pin) and acceleration sensor side ground
(ABD:No.1, ABS:No.15 pin / ECU side ABD:No.39,
ABS:No.30 pin)
(When connector is installed and power is applied)
- Voltage : less than 0.25 V
lCheck voltage among related terminals.
(When connector is installed and power is applied)
- Voltage between ECU (ABD:No.51, ABS:No.10
pin and ABD:No39, ABS:No.30) pin
: 4.75 - 5.25 V
- Signal voltage between ECU (ABD:No.51,
ABS:No.10 pin and ABD:No39, ABS:No.30) pin
: 1.95 V - 3.45 V
(Measure it by laying acceleration sensor horizon
tally and without external force) 43Acceleration Sensor Signal (Signal)

ANTILOCK BRAKE SYSTEM 4F-19
MAINTENANCE AND REPAIR
ON-VEHICLE SERVICE
WHEEL SPEED SENSOR
1 Bolt
2 Front Wheel Speed Sensor
3 Knuckle4 Bolt
5 Rear Wheel Speed Sensor
6 Rear Axle

5A-22 AUTOMATIC TRANSMISSION
CONTROL SYSTEMS
GENERAL
There are two control systems associated with the transmission. The electronic control system monitors vehicle
parameters and adjusts the transmission performance. The hydraulic control system implements the electronic control
system commands.
ELECTRONIC CONTROL SYSTEM
The electronic control system is comprised of sensors, a TCU and seven solenoids. The TCU reads the inputs, and
under software control activates the outputs according to values stored in read only memory (ROM).
The TCU controls the hydraulic control system. This control is via the hydraulic valve body, which contains seven
electro-magnetic solenoids. Six of the seven solenoids are used to control the line pressure, operate the shift valves
and the torque converter lock-up clutch, and to turn on and off the two regulator valves (The two regulator valves
control the shift feel.).
The seventh solenoid is the proportional or variable pressure solenoid (VPS) which works with the two regulator
valves to control shift feel.
Figure 3.1 details a typical TCU control system schematic.
The individual component locations, operation and specifications which make up the electronic control subsystem
are covered in this section.
Figure 3.1 - Typical TCU Control System Schematic

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

AUTOMATIC TRANSMISSION 5A-25
producing a low resistance.
Temperature/Resistance characteristics and location within the solenoid wiring loom are given in tables 3-1 and 3-
2, and figures 3.2 and 3.3.
If the transmission sump temperature exceeds 135°C, the TCU will impose converter lock-up at lower vehicle
speeds and in some vehicles flashes the mode indicator lamp. This results in maximum oil flow through the
external oil cooler and eliminates slippage in the torque converter. Both these actions combine to reduce the oil
temperature in the transmission.
Connects To
Solenoid 1
Solenoid 2
Solenoid 3
Solenoid 4
Solenoid 5
Solenoid 6
Solenoid 7
Solenoid 5
Temp Sensor
Temp SensorWire Color
Red
Blue
Yellow
Orange
Green
Violet
Brown
Green
White
WhitePin No.
1
2
3
4
5
6
7
8
9
10
Table 3.2 - Pin No. Codes for Temperature Sensor Location In Solenoid Loom
Figure 3.3 - Temperature Sensor Location in Solenoid Loom

5A-26 AUTOMATIC TRANSMISSION
Inhibitor
Switch Throttle Position Sensor
The throttle position sensor(TPS) is a resistance potentiometer
mounted on the throttle body of the engine.
It transmits a signal to the TCU proportional to the throttle plate
opening.
The potentiometer is connected to the TCU by three wires:
5 volts positive supply, earth and variable wiper voltage.
Throttle voltage adjustments are as follows:
lClosed throttle voltage is 0.2V to 1.0V.
lWide open throttle voltage is 3V -4.7V.
These measurements are taken between pins 29 and 27 of
the TCU.
Maintaining good shift feel through the transmission life span
is dependant on having an accurate measure of
the engine throttle position. To achieve this the TCU
continuously monitors the maximum and minimum throttle
potentiometer voltages and, if a change occurs, stores the new
voltage values.
However these limits will be lost and will require relearning
should a new TCU be installed, or the throttle calibration data
is cleared by the execution of a particular sequence, This last
instance depends on the installation, and reference should be
made to the Diagnostics Section of this manual. The relearning
will happen automaticallyNotice
Above figure of T.P.S. is for the diesel engine
which is installed on the injection pump.
Gear Position Sensor
The gear position sensor is incorporated in the inhibitor switch
mounted on the side of the transmission case.
(Refer to figure 3.5.) The gear position sensor is a multi-function
switch providing three functions:
lInhibit starting of the vehicle when the shift lever is in a
position other than Park or Neutral
lIlluminate the reversing lamps when Reverse is
selected indicate to the TCU which lever position has
been selected by way of a varying resistance (Refer to
table 3.3.)
Figure 3.5 - Inhibitor Switch

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.

5A-60 AUTOMATIC TRANSMISSION
DIAGNOSIS
DIAGNOSTIC SYSTEM
Recommended Test Equipment and Procedure
The test equipment is designed to be used with the control modules in all vehicles. The components used in the
transmission application are:
lMulti Function Tester, and
lAppropriate vehicle for testing.
Multi Function Tester (MFT)
The MFT is programmed with the special vehicle diagnostic software that allows selection of the unit under test.
The program allows the proper communication to the Transmission Control Unit (TCU).
It then requests information from the user via a menu system to select the required set up.
Examples are viewing codes, clearing error codes, and real-time operation. Set up and operation instructions are
detailed in the user manual.
This equipment can be used by trained personnel such as technicians and mechanics to diagnose electronic and
wiring problems relating to the vehicle transmission. Information that is available includes engine and road (shaft)
speed, transmission oil temperature, throttle position, solenoid/gear status and gear lever position. Current and
stored faults detected by the electronics are also available.
TCU Pin Description
The TCU pin descriptions are listed in table 6.1.1.
The wiring loom pins are shown in figure 6.1.1
Pin
No.
1
2
3
4
5
6
7
8Identification
Common Ground
Do not use
Mode Indicator Lamp -
‘Winter’
Gear Position ‘Park’
Lamp
Gear Position ‘Reverse’
Lamp
Gear Position ‘Neutral’
Lamp
Do not use
Engine Speed Input
Sensor (-Ve)Type
GND
-
OP
OP
OP
OP
-
IPDescription
Main power ground (or the module. Connects
directly to the battery negative terminal.
Indicates ‘WINTER’ mode shift schedule is se-
lected.
Drives the jewel in the instrument cluster to in-
dicate ‘PARK’ gear lever position.
Drives the jewel in the instrument cluster to in-
dicate ‘REVERSE’ gear lever position.
Drives the jewel in the instrument cluster to in-
dicate ‘NEUTRAL’ gear lever position.
Flywheel/Ring gear pulses to indicate engine
speed. 4WD
(Diesel)
O
O
l
l l l
l
4WD
(Gas)
O
O
O
l
l l l
l
l
Table 6.1.1 - TCU Pin Description

AUTOMATIC TRANSMISSION 5A-61
Pin
No.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30Identification
Mode Indicator Lamp -
‘Power’
Throttle Position Sensor
Output as Pulse Width
Modulation for TOD
Air Conditioner Input Signal
Kickdown Switch
Mode Switch
Transfer Case Input
(High) -4WD Lamp High
Ignition Switch
Do not use
Gear Position ‘1’ Lamp/
Gear Position Code 1
*Gear Position ‘2’ Lamp/
Gear Position Code 2*
Gear Position ‘3’ Lamp/
Gear Position Code 3*
Gear Position ‘Drive’
Lamp/
Gear Position Code 4*
CAN (-ve)
CAN (+ve)
K-line Communication Link
Engine Speed Input
Sensor (+ve)
Road Speed Pulses
Shaft Speed Sensor
Signal
Throttle Position Sensor -
Ground
Throttle Position Sensor -
Reference
Throttle Position Sensor -
Input Signal
Transfer(or Case Input
(Low) - 4WD Lamp LowType
OP
OP
-
IP
IP
IP
IP
-
OP
OP
OP
OP
I/O
I/O
I/O
IP
OP
IP
GND
REF
IP
IPDescription
Indicates ‘POWER’ mode shift schedule is se-
lected.
Provides an analogue signal of the throttle po-
sition for the Torque on Demand (TOD) Con-
trol Module.
Input
Switch to indicate when a kickdown is required
at high throttle position.
Switch to select ‘NORMAL’, ‘POWER’ or ‘WIN-
TER’ shift schedule.
Voltage varies from OV to 12V.
Switch to indicate 4WD’HIGH RANGE’ is se-
lected.
Ignition power is used as the main power source
to drive the unit and the solenoids.
Drives jewel in the instrument cluster to indi-
cate
gear leverposition’1'. Drives jewel in the instru-
ment cluster to indicate
gear lever position’2'. Drives jewel in the instru-
ment cluster to indicate gear lever position’3'.
Drives jewel in the instrument cluster to indi-
cate
‘DRIVE’. gear lever position.
CAN low side bus communication (CANL).
CAN high side bus communication (CANH).
Diagnostic information and vehicle coding.
Flywheel/Ring gear pulses to indicate engine
speed.
Road speed signals derived from shaft speed
sensors.
This sensor transmit shaft speed signal to the
TCU.
Throttle position sensor ground.
This is the 5V reference voltage supply gener-
ated by the unit for the throttle position sensor.
This sensor is a resistance potentiometer indi-
cating throttle position.
Voltage varies 0V to 5V.
Switch to indicate 4WD’LOW RANGE’ is se-
lected. 4WD
(Diesel)
O
O
O
O
l
l
l
4WD
(Gas)
O
O
O
O
O
O
O
O
l
l
l
ll
ll
ll
ll
ll
ll
l
l
ll
l
ll
l
l
l
l
ll l

5A-62 AUTOMATIC TRANSMISSION
Identification
Gear Lever Position
Transmission Oil
Temperature
Solenoid 4
Solenoid 1
Do not use
Solenoid 5
Return (-ve)
Gear Lever Position -
Ground
Transmission Oil
Temperature - Ground
Solenoid 6
Solenoid 2
Solenoid 3
Solenoid 7
Do not use
Solenoid 5 (+ve)Type
IP
IP
OP
OP
-
IP
GND
GND
OP
OP
OP
OP
-
OPDescription
This switch has discreet values indicating the
positions selected by the gear shift lever
(PRNDL). Voltage varies 0V to 5V.
Resistive sensor indicates transmission tem-
perature .
High R = low temp
Low R = high temp
Voltage varies 0V to 5V.
On/Off solenoid normally open, combines with
other On/off solenoid 3 for shift quality and se-
quencing.
On/off solenoid normally open, combines with
other On/off solenoid to set the selected gear.
This ensures the earth path for the VPS and
the current in this line is monitored to give feed-
back control of the VPS.
PRNDL switch ground.
Ground reference for temperature sensor in-
put.
On/Off solenoid normally open, sets low/high
line pressure.
On/off solenoid normally open, combines with
other On/off solenoid to set the selected gear.
On/off solenoid normally open, combines with
On/off solenoid 4 for shift quality and sequenc-
ing.
On/off solenoid normally open, locks up the
torque converter to Increase cruising efficiency.
This is the variable force solenoid which ramps
the pressure during gear changes and solenoid
switching, to enhance transmission shift quality. 4WD
(Diesel)
O
O
l
l
4WD
(Gas)
O
O
l
l
ll
ll
ll
ll
Pin
No.
31
32
33
34
35
36
37
38
39
40
41
42
43
44
ll
ll
ll
ll
ll
ll
l= circuit connected
O = circuit not connected
* = unique
OP = Output
IP = Input
I/O = Input/output
GND = Ground
REF = Reference Notice :