Transmission ISUZU TF SERIES 2004 Workshop Manual

7A2-140 DIAGNOSIS (JR405E)
STALL TEST
CAUTION:
Because A/T may break down, do not perform the stall test continuously.

Procedure
1. Chock the four wheels.
2. Warm up the engine.
3. Apply the parking brake.
4. Step on the foot brake fully.
5. Set the select lever to either D, 3, 2, L or R range.
6. Step on the accelerator pedal fully.
7. When the engine speed becomes constant, record tha
t
value quickly.

Stall Speed
Standard: 2600±150 rpm

Evaluation
1. If the stall speed is higher than standard value in all
ranges.

Low line pressure.

Abraded oil pump.

Faulty operation of low clutch.

Adjustment error of or faulty inhibitor switch.


ATF leaking from oil pump, control valve, or
transmission case.

Fixed pressure regulator valve and pilot valve.
2. If the stall speed is higher than standard value in D, 3, 2
and L ranges.

Slip of low clutch.

Slip of low one-way clutch.
3. If the stall speed is higher than standard value in
R
range.

Slip of low & reverse brake.

Slip of reverse clutch.
4. If the stall speed is lower than standard value in all
ranges.

Slip of one-way clutch (in torque converter).

Faulty engine.

DIAGNOSIS (JR405E) 7A2-141
LINE PRESSURE TEST
Procedure
1. Chock the four wheels.
2. Remove the test plug of the transmission case and fit the oil
pressure gauge.
3. Warm up the engine.
4. Apply the parking brake.
5. Step on the foot brake fully.
6.Set the select lever to either D, 3, 2, L or R range.
7. Record the oil pressure at idling.
8. When stepping over the accelerator pedal fully and the
engine speed becomes constant, record the oil pressure
quickly.

Line Pressure
Standard:
Engine Line Pressure (Kpa)
Speed D, 3, 2 or L Range R Range
Idling 350 - 480 450 - 650
Stall 1,050 - 1,250 1.400 - 1,630

Evaluation
1. If the line pressure is lower than standard value at
idling in all ranges.

Abraded oil pump.

Faulty operation of each solenoid.

Sticking of pressure regulator valve or pilot valve.

Fatigued pressure regulator valve or pilot valve spring.


ATF leaking from oil strainer, oil pump, pressure
regulator valve, torque converter relief valve or pressure
relief valve.
2. If the line pressure is lower than standard value at
idling in D, 3, 2 and L ranges.

ATF leaking from low clutch hydraulic circuit.
3. If the line pressure is lower than standard value at
idling in R range.

ATF leaking from reverse hydraulic circuit.

ATF leaking from low and reverse brake hydraulic
circuit.

DIAGNOSIS (JR405E) 7A2-145

5. R range test.
1) Shift into the R range and while starting at full throttle,
check for slipping.
6.P range test.
1) Stop the vehicle on a grade and after shifting into the P
range, release the parking brake. Then check to see tha
t
the parking lock pawl holds the vehicle in place.


Select
Lever
Position
Gear
Position
Gear
Shift
P










R Reverse





N










D 1st
2nd
3rd
4th
3 1st
2nd
3rd
4th(*1)
2 1st
2nd
3rd(*1)
4th(*1)
L 1st
2nd(*1)
3rd(*1)
4th(*1)
Evaluation
1. If there is no 1 to 2 up-shift.

2-4 brake malfunction.

2-4 brake hydraulic circuit failed.

2-4 brake duty solenoid stick.
Refer to symptom diagnosis "No. D1: Faulty Gea
r
Shifting" or DTC section "Gear Ratio Error".

2. If there is no 2 to 3 up-shift.

High clutch malfunction.

High clutch hydraulic circuit failed.

High clutch duty solenoid stick.
Refer to symptom diagnosis "No. D1: Faulty Gea
r
Shifting" or DTC section "Gear Ratio Error".

3. If there is no 2 to 4 (O/D) up-shift.

2-4 brake malfunction.

2-4 brake hydraulic circuit failed.

2-4 brake duty solenoid stick.
Refer to symptom diagnosis "No. D1: Faulty Gea
r
Shifting" or DTC section "Gear Ratio Error".

4. If there is no lock-up in 2, 3 and 4.

Lock-up piston malfunction.

Lock-up hydraulic circuit failed.

Lock-up duty solenoid stick.
Refer to symptom diagnosis "No. I1: No Lock-up"o
r
DTC section "Lock-up Duty Solenoid Failure".


*1: Transmission is shifted at high speed to
prevent engine over-run.

7A2-154 DIAGNOSIS (JR405E)
TCM VOLTAGE CHECK




TCM voltage check is done to check for transmission and TCM
problems which cannot be detected by self-diagnosis.
Additionally, it severs as a back-up check for self-diagnosis.
Measure the voltage drop and make a continuity test for each of
sensors, solenoids and switches.
If the voltage is within the specified range and continuity exists,
that particular area of the TCM and transmission assembly is
normal.
If voltage deviation or lack of continuity is discovered, disconnect
the applicable parts and check of them individually.

Inspection Tool
Use a circuit tester and an oscilloscope to measure voltage and
circuit continuity.
Insert the test probes from the connector wiring side. TCM
terminals are extremely small.
Wrap a piece of thin wire around the probe of tester.
This will make measurement easier.

TCM Pin Assignment












         
 






 




      













 








Connect to White Connector Connect to Grey Connector


No. Wire
Color Pin Name Input /
OutputConnected toMeasurement
Item Measurement
Condition StandardInspection
Point at
Trouble
A1 RED V BATT (Battery Back-up Power
Supply) Input Battery Voltage - 10 – 14.5V Related
harness
At P range 10 – 14.5V Related
harness
A2 YEL/
VIO P Range Switch Input Inhibitor switch Voltage
At other than
P range Less than 2VInhibitor
switch
At brake
stepped 10 – 14.5V Related
harness
A3 RED Brake Switch Input Brake switch Voltage At brake no
stepped Less than 2V Brake switch
At lamp OFF 10 – 14.5V Related
harness A4 PNK/
WHT 3rd Start Indicator Lamp Output 3rd start lamp Voltage
At lamp ON Less than 2V Lamp
A5 GRN K-line signal (Tech 2 serial
communication) Input/
OutputTech 2 - - - Related
harness
A6 - - - - - - - -

ON-VEHICLE SERVICE (JR405E) 7A3-1
SECTION 7A3
ON-VEHICLE SERVICE (JR405E)
TABLE OF CONTENTS
PAGE
Description ...................................................................................................................... 7A3 – 2
Automatic Transmission Fluid (ATF) ............................................................................. 7A3 – 2
ATF Level ......................................................................................................................... 7A3 – 2
ATF Change ..................................................................................................................... 7A3 – 3
Transmission Control Module (TCM) ............................................................................ 7A3 – 4
Throttle Position Sensor ................................................................................................ 7A3 – 5
Inhibitor Switch ............................................................................................................... 7A3 – 6
Speed Sensor .................................................................................................................. 7A3 – 8
Turbine Sensor ................................................................................................................ 7A3 – 9
Power and 3rd Start Switch ........................................................................................... 7A3 – 9
Select Lever ..................................................................................................................... 7A3 –10
Shift Cable ....................................................................................................................... 7A3 –13
Solenoids, Oil Pressure Switch and Oil Temperature Sensor .................................... 7A3 –16
Control Valve Assembly ................................................................................................. 7A3 –18
Flushing the Transmission Fluid Cooler and Line ....................................................... 7A3 –19
Transmission Assembly ................................................................................................. 7A3 –20

7A3-2 ON-VEHICLE SERVICE (JR405E)
DESCRIPTION
Before performing on-vehicle service on the automatic
transmission, check that the engine idling speed and
general engine condition are normal.



AUTOMATIC TRANSMISSION FLUID (ATF)
Inspect
Remove the transmission dipstick to check the condition
of the ATF.
Clean the dipstick and look for gum or varnish.
Gum or varnish indicate scorching of the clutch band
and other parts.
The transmission control module, the transmission unit,
and the vehicle must be carefully checked if gum or
varnish is present.




ATF LEVEL
Inspect
Hot Level
1. Warm up the engine and the transmission by driving
the vehicle on the road so that the temperature
reaches around 80
C (176
F).
Do not turn the engine off.
2. Park the vehicle on a level surface.
3. Apply the parking brake firmly.
4. Let the engine run at idle.
Move the select lever slowly through all the gea
r
ranges.
Stop in each gear range just long enough for the
transmission to engage.
5. Return the select lever to either “P” or “N”.
C07RW009
6. Remove the ATF level dipstick.
7. Wipe the dipstick clean with a paper towel.
8. Reinsert the dipstick and wait several seconds.
9. Remove the dipstick.
The ATF level should be inside the “H” range on the
dipstick.
242R300001
If the ATF level is below the “H” range, ATF must be
added.

ON-VEHICLE SERVICE (JR405E) 7A3-3
Cold Level
The vehicle must not have been driven so that the
temperature reaches around 20
C (68
F) before the
cold level check is made.
1. Park the vehicle on a level surface.
2. Apply the parking brake firmly.
3. Start the engine and allow it to warm up.
The engine coolant temperature gauge needle
should be midway between the “C” mark and “H”
mark.
4. Let the engine run at idle.
Move the select lever slowly through all the gea
r
ranges.
Stop in each range just long enough for the
transmission to engage.
5. Return the select lever either “P” or “N”.
6. Remove the ATF level dipstick.
7. Wipe the dipstick clean with a paper towel.
8. Reinsert the dipstick and wait several seconds.

9. Remove the dipstick.
The ATF level should be inside the “C”range on the
dipstick.
If the ATF level is below the “C” range, ATF must be
added.
242R300002


ATF CHANGE
1. Start the engine and allow it to idle until the ATF
reaches a temperature of 40-50
C
2. Park the vehicle on level ground and block the
wheels.
3. Stop the engine.
4. Raise vehicle and support with suitable safety
stands.
5. Remove the drain plug from the oil pan and drain the
ATF (approximately 6 liters).
6. Remove the oil pan.
7. Inspect the oil pan (details written below).
8. Install the oil pan.
Note:
Use new gasket. Clean the oil pan and magnet.
Oil pan bolt torque : 8 Nm (69 lbin)
9. Replace the gasket and install the drain plug.
Drain plug torque : 35 Nm (26 lbft)
Note:
Do not reuse old washer (gasket).
Clean the drain plug (especially the threaded section).
10. Pour about 5 liters of new ATF. Then, add more ATF
carefully as necessary using the dipstick.
Refer to “ATF LEVEL” previously in this section.
Note:
Keep the engine idle (do not stop it) during the oil level
adjustment.
11. Remove the safety stands and wheel blocks. Inspect
1. Check the drain plug tip for adhesion of foreign
substances.
2. Check the drained ATF for color, smell and inclusion
of foreign substances.
3. Check the oil pan bottom and magnet for adhesion o
f
foreign substances.
If a problem is discovered during those checks, the
Automatic transmission must be overhauled.
Note:
The torque converter and the oil strainer need replaced
with new ones if the drained ATF contains large
amounts of metallic or facing flakes.
In addition, flush the ATF cooler circuit

7A3-4 ON-VEHICLE SERVICE (JR405E)
TRANSMISSION CONTROL MODULE (TCM)



RTW37ALF001901

Remove and Disconnect
1. Disconnect the negative battery cable.
2. Remove the connectors.
3. Remove the fixing nuts and remove the TCM (1)
from the bracket.
Note:
The TCM is fitted under instrument panel of the driver’s
compartment by means of three stud bolts.


Install or Connect
Follow the removal steps in the reverse order. Be
absolutely sure that the connectors are securely
fastened.
AT CONT

7A3-6 ON-VEHICLE SERVICE (JR405E)
INHIBITOR SWITCH
The inhibitor switch is attached to the right side of the
transmission.

Inspect
1. Block the wheels.
2. Disconnect the negative battery cable.
3. Disconnect the harness connectors.
4. Use a ohmmeter to check the inhibitor switch
continuity between the following terminals as shown
in figure.
5. Place the select lever in the “N” range.
249R300001
6. Move the select lever to either side.
Check the inhibitor switch continuity between the
terminals shown in Step (4).
The continuity readings should remain fairly steady
as the select lever is moved.
If there is no continuity or the continuity is
intermittent, the inhibitor switch must be adjusted.

Adjust
1. Disconnect the shift calbe from the lever.
2. Loosen the inhibitor switch bolts.
3. Use the inhibitor switch set plate to align the neutral
holes (manual shaft and inhibitor switch).
Turn the inhibitor switch to adjust it.
Inibitor switch set plate: 5-8840-2763-0
Note:
Inhibitor switch adjustment is very important.
If the inibitor switch is not correctly adjusted, the
automatic transmission will not function normally.



4. Tighten the 2 inhibitor switch bolts to the specified
touque.
Torque: 5.5 N·m (48 lb·in)
47INH-SW01
5. Connect the shift cable to the lever.
6. Connect the harness connector.

Remove or Disconnect
1. Remove the cable bracket (1) from the transmission.
2. Disconnect the shift cable (2) from the lever (3).
3. Disconnect the harness connectors.
4. Remove the inhibitor switch bolts.
5. Remove the inhibitor switch (4) from the
transmission.

238R300001

ON-VEHICLE SERVICE (JR405E) 7A3-7
Install or Connect
1. Install the inhibitor switch (4) to the transmission.
Temporarily tighten the inhibitor switch bolts.
2. Move the manual shaft select lever to the “N” range.

249R300002
3. Use the inhibitor switch set plate to align the neutral
holes (manual shaft and inhibitor switch).
Turn the inhibitor switch to adjust it.
Inhibitor switch set plate: 5-8840-2763-0
Note:
Inhibitor switch adjustment is very important.
If the inhibitor switch is not correctly adjusted, the
automatic transmission will not function normally.
4. Tighten the 2 inhibitor switch bolts to the specified
torque.
Torque: 5.5 N·m (48 lb·in)
47INH-SW01
5. Install the cable bracket (1) to the transmission.
6. Connect the shift cable (2) to the lever (3).
7. Connect the harness connector.
8. Connect the negative battery cable.
9. Remove the wheel blocks.