2004 ISUZU TF SERIES 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) 7A2-143
TIME LAG TEST
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 from N to D or N to R range.
6. Record the time from when moving the select button until
feeling shock.

Time Lag
Standard:
N to D Range: Below 0.7 Seconds
N to R Range: Below 1.2 Seconds

Evaluation
1. If the time lag is out of standard value when shifting N
to D range.

Forward range line pressure is low.

Slip of low clutch.

Slip of low one-way clutch.

Trouble in control valve body (faulty operation, sticking,
clogged oil passage).

Faulty low clutch duty solenoid operation.

Shortage or faulty quality of ATF.
2. If the time lag is out of standard value when shifting N
to R range.

Reverse range line pressure is low.

Slip of low & reverse brake.

Slip of reverse clutch.

Trouble in control valve body (faulty operation, sticking,
clogged oil passage).

Faulty low & reverse brake duty solenoid operation.

Shortage or faulty quality of ATF.

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.

DIAGNOSIS (JR405E) 7A2-155
No. Wire
Color Pin Name Input /
OutputConnected toMeasurement
Item Measurement
Condition StandardInspection
Point at
Trouble
Related
harness
Engine
Speed
Sensor A7 BLK/
RED Engine Speed Sensor Input ECM Voltage (Wave
form) At 2000rpm.
Circuit tester
(+) to A7 pin,
(-) to B5 pin. Pulse
generated (At
AC range
approx. 6.2V)
ECM
A8 - - - - - - - -
A9 - - - - - - - -
Related
harness
Speed
sensor
Speed meter
A10 BLK/
YEL Vehicle Speed Sensor Out (2WD Only) Output Speed meter Voltage (Wave
form) At run in L
range in 1st
gear 20 km/h.
Circuit tester
(+) to A10 pin,
(-) to B5 pin. Pulse
generated (At
AC range
approx. 6.5V)
TCM
At switch
pushed Less than 2VRelated
harness
A11 GRN/
WHT 3rd Start Select Switch Input 3rd start switch Voltage
At switch off 10 – 14.5V 3rd start
switch
At 4L Less than 2VRelated
harness
A12 BLU/
WHT 4L Mode Switch (4WD Only) InputTransfer control
unit Voltage
At other than
4L 10 – 14.5V 4L switch
A13 - - - - - - - -
A14 - - - - - - - -
A15 - - - - - - - -
At fully close Off duty 10%Related
harness
ECM A16 RED/
WHT Throttle Position Sensor Input ECM Wave form
(140Hz Duty
signal) *1
At fully open Off duty 90%Throttle
position
sensor
At 3 range 10 – 14.5V Related
harness
A17 BLK/
GRN 3 Range Switch Input Inhibitor switch Voltage
At other than
3 range Less than 2VInhibitor
switch
At key switch
ON 10 – 14.5V Related
harness
A18 YEL/
BLK DIAG Switch InputData link
connector Voltage
At short circuit
of DIAG
switch Less than 2VRelated
harness
At lamp OFF 10 – 14.5V Related
harness A19 ORG/
BLU A/T OIL TEMP Indicator Lamp OutputAT OIL TEMP
indicator lamp Voltage
At lamp ON Less than 2V Lamp
At lamp OFF 10 – 14.5V Related
harness A20 GRN/
YEL CHECK TRANS Indicator Lamp OutputCHECK TRANS
indicator Lamp Voltage
At lamp ON Less than 2V Lamp
At lamp OFF 10 – 14.5V Related
harness A21 PNK POWER DRIVE Indicator Lamp OutputPOWER DRIVE
indicator lamp Voltage
At lamp ON Less than 2V Lamp
A22 - - - - - - - -
A23 - - - - - - - -

7A2-158 DIAGNOSIS (JR405E)
No. Wire
Color Pin Name Input /
OutputConnected toMeasurement
Item Measurement
Condition StandardInspection
Point at
Trouble
At key switch
ON 10 – 14.5V Related
harness
B24 WHT V ign (Ignition Power Supply) Input Key switch Voltage
At Key switch
OFF Less than 2V Fuse

7.14ms 7.14ms


Time Time
0.714ms 6.426ms
Voltage
Off duty 10% =Throttle Position 0%
Voltage
Off duty 90% =Throttle Position 100%

Engine Speed Sensor Reference Wave Form
Measurement Terminal: A7 (+) B5 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: At engine speed 2000rpm
0V
Vehicle Speed Sensor Output Reference Wave Form
Measurement Terminal: A10 (+) B5 (-)
Measurement Scale: 5V/div 50ms/div
Measurement Condition: Vehicle speed 20km/h at L range
in 1st gear
0V
Turbine Sensor Reference Wave Form
Measurement Terminal: B3 (+) B5 (-)
Measurement Scale: 5V/div 500micro sec/div
Measurement Condition: Vehicle speed 20km/h at L range
in 1st gear
0V
Vehicle Speed Sensor Reference Wave Form
Measurement Terminal: B13 (+) B5 (-)
Measurement Scale: 5V/div 5ms/div
Measurement Condition: Vehicle speed 20km/h at L range
in 1st gear
0V

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

ON-VEHICLE SERVICE (JR405E) 7A3-19
Install or Connect
1. Align the manual valve and the manual plate of the
transmission case.
43ASSY119
2. Install the control valve assembly and tighten the 12
fixing bolts to the specified torque.

Number of bolts Length Color
10 (A) 40 mm (1.57 in) Gold
2 (B) 30 mm (1.18 in) Gold

Bolt torque : 8 N·m (69 lb·in)
3. Connect the 2 harness connectors.
4. If removed, install the oil strainer.
Refer to “Solenoids, Oil Pressure Switch and Oil
Temperature Sensor” previously in this section.
5. Install the new gasket and oil pan.
Bolt torque : 8 N·m (69 lb·in)
6. Fill the fluid.
Refer to “ATF CHANGE” in this section.
7. Connect the negative battery cable.
8. Remove the wheel blocks.

FLUSHING THE TRANSMISSION FLUID COOLER AND LINE
The fluid cooler and lines may be flushed under the
following condition. This will help prevent more trouble
after the transmission is repaired.
1. When the abnormal amount of debris are found.
2. When the abnormal wear or chips on gears and
shafts are found while overhauling.
3. When the abnormal clutch facing wear and oil
contamination are found.

Procedures
1. Block the wheels.
2. Disconnect negative battery cable.
3. Raise vehicle and support with suitable safety
stands.
4. Disconnect fluid cooler lines at transmission case
and fluid cooler.
5. Flush and back-flush the fluid cooler and lines using
solvent and compressed air.
Note:
DO NOT exceed 197 kPa (29 psi) air pressure or
damage may result to oil cooler.

6. Remove all remaining solvent from the system with
compressed air.
7. Flush the cooling system again with Automatic
Transmission Fluid (ATF).
After the final flush, connect all lines.
Cooler line joint connector torque :
44 N·m (33 lb·ft)
8. Replenish ATF
9. Start engine to test the system for the free flow o
f
fluid. If the flow is restricted, the cooler assembly o
r
lines must be replaced.
Repeated cleaning and flushing may not remove all
debris from the fluid cooler circuit.
Move the select lever through the various ranges and
return to neutral.
Check for fluid level.
If the fluid level is below the specified range, ATF
must be added.
10. Connect negative battery cable.
11. Remove safety stands.
12. Remove wheel blocks.