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
AUTOMATIC TRANSMISSION 5A-79
ADJUSTMENTS
HYDRAULIC SYSTEM
The procedures detailed below should be followed in the event that the self test procedure detailed in section 6, or a
defect symptom, indicates that there is a fault in the hydraulic system.
When making adjustments to the transmission, select the appropriate procedures from the following preliminary
checks.
lConduct a transmission fluid test procedure, refer to section 7.2.
lCheck the manual linkage adjustment (refer to the vehicle workshop manual).
lCheck engine idle speed (refer to Section 7.3).
lConduct a stall test (it is outside the scope of this publication to detail this procedure)
lconduct a road test (it is outside the scope of this publication to detail this procedure).
TRANSMISSION FLUID TEST PROCEDURE
Checking Transmission Fluid Level
This procedure is to be used when checking a concern with the fluid level in a vehicle. A low fluid level will result in
gearshift loss or delay if driven when the vehicle is cold.
The vehicle is first checked for transmission diagnostic messages (refer to section 6). If the vehicle has a speedo fault
it is possible for the oil level to be low.
The vehicle is to be test driven to determine if there is an abnormal delay when selecting drive or reverse, or loss of
drive. One symptom of low oil level is a momentary loss of drive when driving the vehicle around a comer. Also when
the transmission fluid level is low, a loss of drive may occur when the transmission oil temperature is low.
If there is no loss of drive when the vehicle is driven warm and a speedo fault is registered, then fluid should be added
to the transmission.
Checking, Adding Fluid and Filling
When adding or changing transmission oil use only Castrol TQ 95 automatic transmission fluid (ATF) or other approved
fluids. The use of incorrect oil will cause the performance and durability of the transmission to be severely degraded.
Do not underfill the transmission. Incorrect tilling may cause damage to the transmission. The fluid level setting
procedure is detailed below.
Notice
When a transmission is at operating temperature hot transmission fluid may come out of the case if the fill plug is
removed. 9 the transmission is at operating temperature allow two hours for cooling prior to removing the plug.
1. If the vehicle is at operating temperature allow the vehicle to cool down for two, but no greater than four hours
before adding transmission fluid (this will allow the transmission to be within the correct temperature
range).
While hot the ATF level is higher and removing the plug may result in oil being expelled from the filler hole. This
will result in the level being low.
2. The transmission selector is to be in Park.
Switch the engine off.
3. Raise the vehicle on a hoist (or leave over a service pit).
4. Clean all dirt from around the service fill plug prior to removing the plug. Remove the oil service fill plug.
Clean the fill plug and check that there is no damage to the ‘O’ ring.
Install the filler pump into the filler hole.
5. Lower the vehicle with the filler pump still connected and partially fill the transmission.
Start the vehicle in Park with the Parking brake and foot brake applied with the engine idling, cycle the transmission
gear selector through all positions, adding ATF until gear application is felt.
5A-80 AUTOMATIC TRANSMISSION
6. Switch off the engine and raise the vehicle on the hoist, if applicable, ensuring that the vehicle is level.
7. Three minutes after the engine has stopped, but no longer than one hour, remove the filler pump, The correct
level is reached when ATF is aligned with the bottom of the filler hole. If the correct level is not reached, then add
a small quantity of ATF to the correct level.
8. Replace the transmission filler plug and clean all remnants of ATF on the transmission and vehicle.
9. Tighten the transmission filler plug to specification.
Checking, Adding Fluid and Filling - Drained or Dry Transmission
To set the correct fluid level proceed as follows.
1. Set the transmission selector to Park and switch the engine off.
2. Raise the vehicle on a hoist (or leave over a service pit).
3. Clean all dirt from around the service fill plug prior to removing the plug, Remove the oil service fill plug. Clean the
fill plug and check that there is no damage to the ‘O’ ring. Install the filler pump into the filler hole.
4. Lower the vehicle with the filler pump still connected and partially fill the transmission. This typically requires
approximately :
a. If the transmission torque converter is empty:
9.0 litres - 4WD
9.0 litres - RWD
b. If the transmission torque converter is full:
4.5 litres - 4WD
4.5 litres - RWD
5. Start the vehicle in Park with the Parking brake and foot brake applied with the engine idling, cycle the transmission
gear selector through all positions, adding ATF until gear application is felt.
6. Then add an additional 0.5 litres of ATF.
7. Switch off the engine and raise the vehicle on the hoist. Remove the filler pump and replace the filler plug. The
plug shall be tightened to specification.
8. The vehicle is then to be driven between 3.5 and 4.5 kilometers at light throttle so that the engine does not
exceed 2500 rpm. This should result in the transmission temperature being in the range 50 to 60°C.
9. With the engine idling, cycle the transmission selector through all gear positions with the brake applied.
10. Stop the engine. Raise the vehicle on the hoist, if applicable ensuring the vehicle is level.
11. Three minutes after the engine has stopped, but no longer than one hour, remove the filler plug. The correct
level is reached when ATF is aligned with the bottom of the filler hole. If the correct level is not reached, then add
a small quantity of ATP to the correct level.
12. Replace the transmission filler plug and clean all remnants of ATF on the transmission and vehicle. Tighten the
transmission Filler plug to specification.
ELECTRONIC ADJUSTMENTS
Idle Speed Adjustment
Carry out the adjustments to the idle speed as detailed in the workshop manual.
Throttle Position Calibration
Should the throttle position data stored in the TCU be lost or be out of specification, as indicated by a diagnostic
trouble message, it may be re-established by the following procedure.
lCheck that the hot engine idle speed is within specification.
lAllow the engine to idle in ‘Drive’ for 60 seconds with the air conditioner (if fitted) turned off. The closed throttle
reference point in the TCU has now been set.
Switch the engine off but leave the ignition on. Hold the accelerator pedal on the floor for 60 seconds. The wide open
throttle reference point in the TCU has now been set.