engine SSANGYONG MUSSO 1998 Workshop Repair Manual

5A-54 AUTOMATIC TRANSMISSION
POWER FLOW - DRIVE 3 AND MANUAL 3
In Drive 3 and Manual 3, transmission drive is via the input shaft to the forward clutch cylinder. The elements of the
transmission function as follows :
lThe C2 clutch is engaged to drive the forward sun gear.
lThe C1 clutch is engaged to drive the planet carrier.
lThe forward sun gear and the planet carrier are driven clockwise at the same speed therefore there is no
relative motion between the sun gear and the pinions.
lThe ring gear and output shaft are driven in a clockwise or forward direction at input shaft speed.
lThe C4 clutch is applied to bypass the 3-4 OWC and provide engine braking on overrun.
Control
To maintain this arrangement in the steady state solenoids and valves are activated as follows:
lSolenoid S1 is switched Off. S2 is switched Off.
lWith S1 and S2 switched Off, the 2-3 and 3-4 shift valves are held in the third gear position by line 500
pressure.
lThe 1-2 shift valve is held in the third gear position by S1-S2 oil pressure.
l2nd oil (line pressure) from the 1-2 shift valve is directed to the band apply regulator valve. and to the 2-3 shift
valve.
lThe band apply regulator valve supplies 2nd oil (regulated to line pressure multiplied by the valve ratio) to the
band apply feed (BAF) circuit.
lBand apply feed oil is directed to:
- The outer apply area of the front servo
- The 1-2 shift valve to provide an exhaust port when the transmission is shifted to first gear
- The 3-4 shift valve for use when the transmission is shifted into fourth gear
l2nd oil at the 2-3 shift valve is directed to the 3rd oil circuit.
l3rd oil from the 2-3 shift valve is directed to the clutch apply regulator valve, and to the 4-3 Sequence Valve.
lThe clutch apply regulator valve supplies oil (regulated to line 500 pressure multiplied by the valve ratio) to the
clutch apply feed (CAF) circuit.
l The CAF oil is directed to:
- The C1 clutch
- The C1 bias valve
- The 4-3 sequence valve
lAt the 4-3 sequence valve the CAF oil becomes band 1 release feed (B1R-F) oil, and is directed through the
3-4 shift valve to the spring end of the 4-3 sequence valve, and to the release side of the front servo piston to
hold band 1 off.
lDrive (line pressure) is routed through the 3-4 shift valve to apply the C4 clutch.
Refer to figure 5.6 and table 5.7.
Table 5.7 - Engaged Elements - Drive 3 and Manual 3
Gear State
Drive 3 and Manual 3C1
XC2
XC3
-C4
XB1
-B2
-1-2
OWC
-3-4
OWC
XLU
CLUTCH
- ELEMENTS ENGAGED

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-64 AUTOMATIC TRANSMISSION
Default Transmission Operating Modes
The TCU relies on accurate information from its inputs and complete control of its outputs to effectively control the
transmission. To ensure that it has both valid inputs and functioning outputs, the TCU carries out both hardware and
software fault detection routines. The TCU will respond to any faults detected by adopting the operating modes which
are detailed below.
The following symptoms of faults are the most obvious results of each fault under ‘normal’ conditions.
There is always the possibility that a fault may not be detected. If undetected fault conditions are present, the
operation of the transmission is difficult to predict.
1 Throttle Fault
lAll shifts will occur as if a nominal throttle (approx. 44%) were applied for shift scheduling.
lAll shifts will be firm as full throttle and hence high engine torque is assumed.
lThe torque converter will be unlocked at all times.
lAll downshifts initiated by the shift lever will occur as though they were ‘automatic’ shifts. That is the engine
braking effect will not occur until near the end of the shift.
lLine pressure will always stay high (solenoid 6 OFF) to cope with assumed high throttle/torque.
If a fault is undetected, the percent throttle is most likely to be interpreted as higher than actual, resulting in late
upshifts, early downshifts, firm shifting and a harsh 3-1 shift when stopping.
2 Throttle Not Learnt Fault
The transmission operates from default throttle calibration values which results in the evaluation of the throttle being
higher (more open) than it is. There(ore at zero throttle settings, the transmission may calculate that sufficient throttle
opening is present to justify high line pressure and switch solenoid 6 to OFF.
Other symptoms are:
a. late upshifts and
b. lock-up maintained at zero throttle when the vehicle speed is sufficiently high.
3 Engine Speed Fault
lAll shifts will be firm because an engine speed corresponding to peak engine torques is assumed.
If a fault is undetected, the engine speed is likely to be interpreted as stalled resulting in soft shifting possibly with an
end of shift bump.
4 Vehicle Speed Sensor Fault
lAll shifts will be controlled by the shift lever with skip downshifts disabled and downshifts only allowed if the
engine speed is low. Fourth gear will be inhibited.
lThe torque converter will be unlocked at all times.
If a fault is undetected, the vehicle is likely to be interpreted as being stationary resulting in first gear operation at all
times. Note that speedometer transducer faults are likely to cause the vehicle’s speedometer to become inoperative.
5 Gear Lever Fault (Inhibitor/PRNDL Switch)
lThe gear lever is assumed to be in the Drive position.
lThe transmission is limited to 2nd,3rd, and R gears only.
lThe rear band will apply at all times when the lever is shifted to P, R or N. (B2 inhibition and reverse lockout
protection is disabled.)
lThe torque converter will be unlocked at all times.
lManually (gear lever) initiated downshifts will not be available.
If a fault is undetected, the gear lever position is likely to be interpreted as being higher than actual. Where Park is the
highest position and Manual 1 is the lowest, the result being the availability of higher gears than selected by the gear
lever.

AUTOMATIC TRANSMISSION 5A-67
Table 6.1.3 - Diagnostic Trouble Messages
Description / Cause
There have been no faults recorded since the TCU was last cleared. If
the fault history has never been cleared, then there have been no
faults recorded since the TCU was originally powered up.
There is an internal fault within the TCU.
The voltage measured by the TCU corresponding to the battery sup-
ply voltage has been outside the range of the maximum operating
voltage of 16.5 volts.
The minimum operating voltage depends on the transmission tem-
perature but is typically between 8-9 V for a warm transmission.
The voltage measured by the TCU from the throttle potentiometer has
been outside acceptable levels.
This would typically indicate a loose connection in the wiring to, or
within, the throttle sensor which has caused the signal at the TCU to
read 0V or 5V.
The voltage measured by the TCU across the temperature Input ter-
minals has been outside acceptable levels.
This would typically be caused by a loose connection or short to ground
in the wiring to, or within, the temperature sensor which has caused
the signal at the TCU to read 0V or 5V.
The voltage measured by the TCU across the shift lever input termi-
nals has been outside acceptable levels for a significant length of
time. This would typically be caused by a loose connection or short to
ground in the wiring to, or within, the inhibitor switch which has caused
the signal at the TCU to read 0V or 5V.
The signal from the ignition, of ignition pulses, has either been non-
existent or has been unreliable.
There are two reasons this fault could occur. The first is due to a lack
of ignition pulses when other TCU inputs would indicate that the en-
gine is running, that is the gear lever is in a driving position, the throttle
is applied and vehicle speed increasing.
The second cause of this (aunt is the frequency of the pulses of the
ignition pulse input to the TCU indicate an unachievable engine speed.
The pulses from the shaft speed sensor have either been non-exis-
tent or have been unreliable.
There are three reasons this fault could occur. The first is due to a
sudden loss of speedometer pulses at a time when they were fre quent,
thus indicating an unachievable degree of deceleration of the drive
line. The second cause of this fault is that the frequency of the pulses
on the shaft speed sensor input to the TCU indicate an unachievable
propeller shaft speed. The third is the presence of a high engine speed
in a driving gear with no speedometer pulses. Condition
Test Pass
Transmission Control
Module Fault
Battery Voltage Input
Fault
Throttle Input Fault
Temperature Input Fault
Shift Lever Position
Input Fault
(Inhibitor/PRNDL Switch)
Engine Speed Sensor
Fault
Shaft Speed Sensor
Fault
(Speedo Sensor)Solenoid
1
2
3
4
5
6
7
8

5A-68 AUTOMATIC TRANSMISSION
Description / Cause
The signal from the mode switch is unreliable.
This fault is caused by too many changes in the mode input signal
over a period of time. Typical causes would be an intermittent connec
tion in the switch or wiring or an intermittent short to ground in the
wiring.
The data link between the TCU and the engine management module
is found to be unreliable because the checksum, or the data received,
did not match the correct checksum.
This could be caused by an open circuit, short circuit to ground or a
loose connection in the link wire itself.
Each solenoid in turn is switched off if it was energised, or switched on
if it was not energised by a very small 100 ms pulse. This pulse is too
short for the solenoid to react so transmission operation is not af
fected.
The solenoid feedback voltage is measured before the 100 ms pulse
and again during the pulse. If the difference is outside the acceptable
limits the relevant fault messages are set.
Typical causes would be an open circuit in the wiring to or within the
solenoid, or a short circuit to ground in the wiring to, from or within the
solenoid in question.
If several of these fault codes are presents check the wiring or
connectors that are common to the selected solenoids, especially the
earth connections.
The state of the solenoid feedback voltage is outside acceptable
limits but the faulty solenoid could not be isolated.
The current to solenoid 5 was outside acceptable limits.
This fault results from a mismatch between the current set point for
solenoid 5 and the current measured by the feedback within the TCU.
Typical causes would be an open circuit or short circuit to ground in
the wiring to, from or within the solenoid. It is also possible that there
has been a fault in the solenoid output circuit. If this is the case
however, the fault should be continually present.
The closed throttle position has not been learnt. This fault
may be caused by the transmission not having reached normal
operating temperature or the engine idle speed being incorrect.
The TCU will learn the closed throttle position automatically
when the transmission is brought to normal operating
temperature and the engine is allowed to idle in Drive with the
‘base idle’ correctly set and the air conditioner (if fitted)
switched off. Condition
Mode Switch Input Fault
(Power/Economy Mode)
Data Output Link Fault
On/off Solenoid Fault
(Solenoid 1,2,3,4,6,7)
Solenoid 5 Fault
(Variable Pressure
Solenoid)
Throttle Not LearntSolenoid
9
10
11
12
13

AUTOMATIC TRANSMISSION 5A-69
MECHANICAL TESTS
In Vehicle Transmission Checks
Carry out the following tests before removing the transmission.
lSee Checking Transmission Fluid Level, Section 7.2.1.
lCheck that the transmission oil is not burnt (colour and smell are correct).
lEnsure that the transmission is not in limp home mode (LHM).
lCheck that the battery terminals and the earth connections are not corroded or loose.
lCheck the engine stall speed is within the handbook value.
lCheck that the cooler flow is not restricted.
lCheck that all electrical plug connections are tight.
lCarry out a road test to confirm the symptoms, if necessary.
lInspect the oil, ensure that there are no metal or other contaminants in the oil pan.
Diagnosing Oil Leaks
Determine the source of oil leaks by firstly cleaning down the affected area, then driving the vehicle.
Inspect the seals to confirm the source of the leak.
lTo determine the source of a rear servo oil leak, raise the vehicle on a hoist, then carry out a reverse stall.
lTo determine the source of a front servo leak, raise the vehicle on a hoist, then run the vehicle in second gear.
Troubleshooting Charts
The troubleshooting charts are set out as follows:
lTable 6.2.1 Drive Faults,
lTable 6.2.2 Faulty Shift Patterns.
lTable 6.2.3 Shift Quality Faults.
lTable 6.2.4 After Teardown Faults.
Table 6.2.1 - Drive Faults
Action
Check the fluid level. Top up as necessary.
Inspect and clean C1/C2 feed.
Reinstall/renew the ‘z’ link.
Remove, clean and re-install the PRV.
Inspect and replace as necessary.
Inspect and replace as necessary.
Inspect and replace as necessary.
Check servo adjustment or replace rear band
as necessary.
Check for failure in C3, C3 hub or C1/C2 cylin-
der. Repair as necessary.
Inspect and clean PRV.
Inspect and replace pump gears as necessary.
Inspect and repair as necessary. Possible Cause
Insufficient auto transmission fluid.
Blocked feed in C1/C2 cylinder.
‘Z’ link displaced.
Primal regulator valve (PRV) jammed open.
Overdrive shaft or input shaft seal rings
failed.
3-4 or 1-2 one way clutch (OWC) installed
backwards or failed.
C2 piston broken or cracked.
Rear band or servo faulty.
Failure in C3, C3 hub or C1/C2 cylinder.
Jammed primary regulator valve (PRV).
Damaged/broken pump gears.
Dislodged output shaft snap ring.Symptom
No Drive in D
No Drive in
Reverse
No engine braking
in Manual 1
Engine braking in
Manual 1 is OK
No drive in Drive
and Reverse

AUTOMATIC TRANSMISSION 5A-75
SELF DIAGNOSIS TEST
1. Turn the ignition switch to “OFF” position.
2. Connect the scanner harness connector to the engine
compartment diagnosis socket.
3. Turn the ignition switch to “ON” position.
4. Select “Electronics control vehicle diagnosis” from the
function selection display and press “Enter”.
5. Select “Musso(98 face lift)” from the vehicle model selection
model selection display and press “Enter”.
6. Select “Transmission control unit(TCU)” from the control
system selection and press “Enter”.
7. Select “Self-diagnosis” from diagnosis items.
Notice
Check sensor output value displays if necessary.
8. Determine the fault code and check the detective Items.
Notice
Refer to sefadf3fnosfs list.

5A-76 AUTOMATIC TRANSMISSION
Action
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck voltage between terminal 27 and 29 of TCU,
- Standard value : 0.2 - 4.7V
lCheck TPS.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck engine speed sensor.
lCheck resistance between terminal 8 and 24 of TCU (when the
connector is disconnected).
- Standard value : 1 .9 - 0.2 k
W
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck vehicle speed sensor.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck engine speed sensor.
lCheck inhibitor switch resistance between terminal 34 and 37 of
TCU(when the connector is disconnected).
- Standard value : 1st gear - 4 - 4.4 k
W
2nd gear - 4,8 - 2.2 kW
3rd gear - 3 - 3.4 kW
D gear - 4.5 - 4.g kW
N gear - 6.8 - 7.2 kW
R gear - 10.8 -11.2 kW
P gear - 18.6 - 19 kW
lCheck voltage between terminal 31 and 37 of TCU.
- Standard value : 0-5V(P,R,N,D,L)
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck mode switch.
lCheck condition between terminal 1 and 13 of TCU.
Winter mode :12V, Normal mode : Open status, Power mode : 0V
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck voltage between terminal 32 and 38 of TCU.
- Standard value : 0-5V
lCheck oil temperature sensor.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck battery condition.
lCheck alternator. Possible Cause
Throttle position sensor
Engine RPM
Vehicle speed
Shift lever
W, E, P mode switch
T/M oil temperature
Battery voltage Symptom
P1702
P1703
P1704
P4705
P1706
P1707
P1708
Self-diagnosis List

AUTOMATIC TRANSMISSION 5A-77
Action
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck voltage between terminal 4 and 11 of TCU.
- Standard value : when the A/C compressor is ON : 12V
when the A/C compressor is OFF : 0V
lCheck cable for open / short,
lCheck connection of other connectors.
lCheck voltage between terminal 1 and 12 of TCU.
- Standard value : when the kick down switch is ON : 12V
when the kick down switch is OFF : 0V
lFully depress accelerator pedal for 5 seconds(ignition key is ON).
lRelease accelerator pedal.
lDepress brake pedal and start the engine in ‘P’ position.
lDepress brake pedal and idle the engine for 5 seconds in ‘D’
position.
lShift into ‘D’ position and determine fault code for throttle initial-
ization.
lComplete the initialization.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck resistance between terminal 1 and 34 of TCU(when the
connector is disconnected).
- Standard value : 26 - 30
W
lCheck solenoid.
lCheck cable for open / short.
lCheck connection of other connectors,
lCheck resistance between terminal 1 and 40 of TCU (when the
connector is disconnected).
- Standard value : 26 - 30
W
lCheck solenoid.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck resistance between terminal 1 and 41 of TCU (when the
connector is disconnected).
- Standard value : 26 - 30
W
lCheck solenoid.
lCheck cable for open / short.
lCheck connection of other connectors.
lCheck resistance between terminal 1 and 33 of TCU (when the
connector is disconnected),
- Standard value : 26 - 30
W
Possible Cause
Air conditioner switch
Kick down switch
Pedal
Vehicle ID
VPS offset
Throttle position sensor
initialization
Solenoid 1
Solenoid 2
Solenoid 3
Solenoid 4 Symptom
P1710
P1712
P1713
P1714
P1715
P1716
P1733
P1734
P1735
P1736