2004 ISUZU TF SERIES sensor

DIAGNOSIS (JR405E) 7A2-123
Step Action Yes No
6 Check of power supply to and earth of TCM.
Are the power supply and earth proper?



TCM
A1 (+B)
B5
B15
H23
(15)C95
(5)
(15) BLK/YEL
BLK BLK Battery
C94
(1)
BLK
Go to Step 7
Check the power
source harness and
earth harness (bolt
tightening to the
body).
7 Inspection of speed sensor and turbine sensor
Have the speed sensor and turbine sensor failed at the same
time? (No DTC is stored at the time of trouble) Repair the defect or
replace. Go to Step 8
8 Is the stall revolution correct in D, 3, 2 and L range? Refer the
STALL TEST section in this manual.
Go to Step 9
Repair the defect or
replace.
9 Is the line pressure correct? Refer the LINE PRESSURE TEST
section in this manual. Trouble in the AT
assembly or control
valve.
Repair the defect or
replace.

7A2-124 DIAGNOSIS (JR405E)
No. E2: Only 4th gear (O/D) is Not Selectable

Description:

Gear is not shifted up from 3rd to 4th though the vehicle is accelerated.

Possible Cause:

Disordered select cable.

Disordered inhibitor switch.

ATF thermo sensor detects low oil temperature (4th gear is prohibited temperature less than 10C.).

Clogged oil passage of low clutch duty solenoid.

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

Step Action Yes No
1 Dislocation or disordered of select lever.
Does the vehicle move when the brake is released in a position
other than the P range and the vehicle is pushed?
Go to Step 2
Adjust the select
cable.
2 Gear ratio trouble diagnosis.
Travel in the following sequence for about 7 seconds or more in
each range: Start in the L range (1st) to 2 range (2nd) to 3 range
(3rd) to D range (4th) (to detect the gear ratio trouble exactly, this
process should be carried out)
Go to Step 3 Go to Step 3
3 Are any DTCs stored?
Go to DTC Chart Go to Step 4
4 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.

Go to Step 5
If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.
Overhaul the AT
unit.

DIAGNOSIS (JR405E) 7A2-125
Step Action Yes No
5 Inspection of inhibitor switch using a Tech 2 or circuit tester.
When the select lever is operated, is the data display in the Tech
2 correct or voltage at each range correct?
Inhibitor SW

TCM
A2 (P)
A17 (3)
B2 (2)
B10 (N)
B11 (D)
B19 (R)
B21 (L)
C95
(2 )
(10)
(11 )
(19)
(21) Y E L /V IO
RED/BLK
BLUBLK/GRN
Starter Relay
C94
(2 )
(3 )
BH22
(1)
(6)
(4)
(7)
(5)
(2) P
2
R
N
D
3
L
Start SW
PNK/BLU
E51
(2)
(4)
(8)
(5)
(1)
(9)
(6)
(3)
(10)
(7)
(38)
(15)
(3)
(37)
H4PNK/BLK
RED/YEL Y E L /V IO
BLK/GRN
PNK/BLK RED/BLK
BLU RED/YEL
PNK/BLU
BLK/WHT
BLK
BLK BLK/WHT Key Switch WHT
WHT
ICU (W/ Immobilis e r)
Ground (W/O Immobilis e r)
TCM terminal
RangeA2 B19 B10 B11 B17 B2 B21
P10 –
14.5V-- - - - -
R-10 –
14.5V-- ---
N--10 –
14.5V----
D - - - 10 –
14.5V---
3----10 –
14.5V--
2-----10 –
14.5V-
L------10 –
14.5V
Go to Step 6
Adjust the inhibitor
switch.
6 Inspection of ATF oil thermo sensor.
Is the ATF oil temperature sensor terminal voltage correct?
After running using the Tech 2 data display function, is the ATF
temperature higher than 10C?

ATF
Te m p .
SensorTCM
B4 (+)
B14 (-)
H23
(8 )
(3 )C95
(4)
(14) BLU Te rm i n a l
Assembly
BLU/BLKE54
(2 )
(8 ) BLU
BLU/BLK
TCM terminal
Temperature (deg. C)
B4 (Output voltage)
201.55
401.08
600.7
800.5
1000.3
1200.2Go to Step 7
Repair the defect or
replace.
7 Is the stall revolution correct in D, 3, 2 and L range? Refer the
STALL TEST section in this manual.
Go to Step 8
Repair the defect or
replace.
8 Is the line pressure correct? Refer the LINE PRESSURE TEST
section in this manual. Trouble in the AT
assembly or control
valve.
Repair the defect or
replace.

DIAGNOSIS (JR405E) 7A2-127
No. F1: Low Maximum Speed or Poor Acceleration

Description:

Starting acceleration is poor.

Acceleration is slow though the accelerator pedal is stepped on during the running.

Diagnosis Hints:

In addition to the low engine output, faulty gear shifting of AT or fixing at the 3rd position may be possible.
Therefore, in case of such a trouble that "maximum speed is low, and acceleration is poor", it should be cleared
up whether the trouble is originated from the engine system of AT system by a running test, inspection of stall
revolution, etc.

Possible Cause:

Clogged air cleaner, out of injection timing, dropped compression pressure, etc.

Fixing at 3rd position (fail-safe activated).
Since the gear is fixed at the 3rd position because of the fail-safe function, a trouble that "Maximum
speed is low, and acceleration is poor" is resulted. In this case, the DTC is memorized.
When TCM stops operation because of faulty TCM ground, the gear is fixed at the 3rd position because
of a mechanical reason. In this case, no DTC is memorized.

Disordered inhibitor switch .

Incorrect properties of throttle opening signal (serial communication) of throttle position sensor.
Throttle opening signal (serial communication) of the throttle position sensor does not change in
proportion to the throttle opening. In this case, fixing at the high or low gear results in such a trouble
that "Maximum Speed is Low and Acceleration is Poor".

Slip of clutch (low clutch, high clutch).

If slip of clutch is caused, a DTC (gear ratio error) is stored.

Dropped line pressure.

Trouble in the torque converter system (faulty operation).

Step Action Yes No
1 Test Drive.
Is the gear smoothly shifted in the order of 1st to 2nd, 2nd to 3rd,
3rd to 4th gear and lock up?
Clogged air
cleaner, out of
injection timing,
dropped
compression
pressure, etc. Go to Step 2
2 Gear ratio trouble diagnosis.
Travel in the following sequence for about 7 seconds or more in
each range: Start in the L range (1st) to 2 range (2nd) to 3 range
(3rd) to D range (4th) (to detect the gear ratio trouble exactly, this
process should be carried out)
Go to Step 3 Go to Step 3
3 Are any DTCs stored?
Go to DTC Chart Go to Step 4

DIAGNOSIS (JR405E) 7A2-129
Step Action Yes No
6 Inspect the output voltage and throttle opening signal of the
throttle position sensor using a Tech 2 or circuit tester.
Is a voltage value in proportion to the throttle opening output?




TPSTCM
A16
C56
(28)C94
(16) RED/ WHT
C56
(49)
(38)
(57)
(69)ECM
A47 (GND)
A35 (Out put )
A26
A55 (+5V)
A69 (I dl e SW)
Go to Step 7
Repair the defect or
replace.
7 Check of power supply to and earth of TCM.
Are the power supply and earth proper?




TCM
A1 (+B)
B5
B15
H23
(15)C95
(5)
(15) BLK/YEL
BLK BLK Battery
C94
(1)
BLK
Go to Step 8
Check the power
source harness and
earth harness (bolt
tightening to the
body).
8 Is the stall revolution correct in D, 3, 2 and L range? Refer the
STALL TEST section in this manual.
Go to Step 6
Repair the defect or
replace.
9 Is the line pressure correct? Refer the LINE PRESSURE TEST
section in this manual. Trouble in the AT
assembly or control
valve.
Repair the defect or
replace.

DIAGNOSIS (JR405E) 7A2-133
No. G4: Large Noise During Idling with the Vehicle in Stop State

Description:

The transmission is noisy during the idling speed in all ranges.

Diagnosis Hints:

Causes such as solenoid operating sound or faulty oil pump are considered.

Distinguishing to some extent is possible by stopping the solenoid operation temporarily, checking the correlation
for the former case and, changing the line pressure and confirming the correlation with noise.

As a matter of course, noise may be generated around the engine, for instance, other than the AT and should be
checked carefully.
Note:
When the noise is generated only at the time of gear shift, it may be the sound of flowing ATF or gear
noise. If the sound varies depending on the gear speed to be shifted, it may be the gear noise generated
from the planetary gear and its related components. If the sound varies depending on the vehicle
speed, it may be the gear noise of the output system, and if varying depending on the engine speed, it
may be the gear noise of the input system or faulty torque converter.
In either case, sound may be "noise" depending on the origin and resonance object. When the object
generating the sound (resonance object) and the sound source (vibration source) are different,
investigation of the cause may be difficult.





No. H1: Judder Occurs at the Lock-up

Diagnosis Hints:

The vehicle body judders at lock-up.

Diagnosis Hints:

Slip due to burning of the lockup piston or insufficient fastening due to dropped working pressure are considered.
Trouble diagnosis flow is basically the same as "No. I1: No lock-up".
Note:
When the lock-up piston has burnt, foreign material mixed in the oil cooler is considered. In such a
case, inspect the oil cooler circuit for clogging of the oil cooler.





No. H2: Large Lock-up Shock
No. H3: Lock-up Point is High or Low

Description:

Large shock is felt at lock-up.

Lock-up point is excessive high or low.

Diagnosis Hints:

Out of properties of input sensor or faulty lock-up piston pressure system are considered.

Trouble diagnosis flow is basically the same as "No. I1: No lock-up".

7A2-134 DIAGNOSIS (JR405E)
No. I1: No Lock-up

Description:

Lockup is not performed in spite of the lock-up area.

Diagnosis:

Lockup is not performed in spite of the lock-up area.

Monitor the signal to the lock-up solenoid while carrying out a running test.

When the output signal to the lock-up solenoid is correctly sent causing no lock-up, clogged lock-up solenoid oil
passage or malfunction of the lock-up piston may be considered.

Even the lock-up area, the output signal to the lock-up solenoid is not sent, fault of the ATF thermo sensor
controlling the lockup is considered. (Lock-up is not operated at ATF temperature less than 11C or more than
128C.)
Note:
When the lock-up piston has burnt, foreign material mixed in the oil cooler is considered. In such a
case, inspect the oil cooler circuit for clogging of the oil cooler

Possible Cause:

ATF thermo sensor detects low oil temperature (Lock-up is prohibited temperature less than 10C.).

Clogged oil passage of lock-up duty solenoid.

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

Step Action Yes No
1 Are any DTCs stored?
Go to DTC Chart Go to Step 2
2 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.

Go to Step 3

If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.
Overhaul the AT
unit.

DIAGNOSIS (JR405E) 7A2-135
Step Action Yes No
3 Inspection of electrical or mechanical fault
When the ATF oil temperature is above 20C and the vehicle
speed is 80km/h, is ON signal issued to the lock-up solenoid
using the Tech 2 or circuit tester?
Control Valve

TCM
B17
B23 BLK Lock-up Solenoid

Terminal
Assembly
VIO Line Pressure Solenoid

E54
(4)
(6)H23
(14)
(6)C95
(17)
(23) BLK
VIO
TCM terminal
Lock-upB17
At lock-up Approx. 2.2 - 9.0V (AC range)
At unlock-up Approx. 1.0 – 2.0V (AC range)
Clogged oil
passage of lock-up
solenoid or faulty
operation of lock-
up piston. Go to Step 4
4 Inspection of ATF oil thermo sensor.
Is the ATF oil temperature sensor terminal voltage correct?
After running using the Tech 2 data display function, is the ATF
temperature higher than 10C?

AT F
Te m p .
SensorTCM
B4 (+)
B14 (-)
H23
(8)
(3)C95
(4)
(1 4) BLU Te r m in a l
Assembly
BLU/BLKE54
(2)
(8) BLU
BLU/BLK
TCM terminal
Temperature (deg. C)
B4 (Output voltage)
201.55
401.08
600.7
800.5
1000.3
1200.2
Monitor the electric
system input
sensor signal and
find a signal
causing no lockup.
Repair the defect or
replace.