clutch ISUZU TF SERIES 2004 Workshop Manual

7A2-56 DIAGNOSIS (JR405E)
Reference:
When the high clutch duty solenoid is operated, following signal is outputted.
Measurement terminal: B8 (C95) and B22 (C95)
-AC range by circuit tester: Approximately 6.2V
-Oscilloscope: Following wave form can be found.

High Clutch Duty Solenoid Reference W ave Form
Measurement Terminal: B8 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: P, N range in idle
Measurement Terminal: B8 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: D range 3rd, 4th gear
0V 0V

DIAGNOSIS (JR405E) 7A2-57
DTC P0768 (Flash Code 34) Low Clutch Duty Solenoid Failure



C ontrol Valve

TCM
B6
B7
B8
B9
B22 (GND)
BLU/BLK
WHT/BLU
L&R Brake Solenoid

Term inal
Assembly
BLK/YEL
RED
2-4 Brake Solenoid

High Clutch Solenoid

Low Clutch Solenoid

E54 (5)
(9)
(10) (3)
(11)H23 (11)
(5)
(7)
(2)
(1)
GRY/REDC95
(6)
(7)
(8)
(9)
(22)
BLU/BLK
BLK/YEL RED
WHT/BLU
GRY/RED

7A2-58 DIAGNOSIS (JR405E)
Gear Position & Shift Solenoid Operation


Range TCM terminal

Gear B8
(High clutch
solenoid) B9
(Low clutch
solenoid) B7
(2-4 brake
solenoid) B6
(Low & reverse
brake solenoid)
P 

R Reverse


N 

D, 3, 2 1st

2nd


3rd


4th


L 1st


2nd


3rd


4th


: On (Operated)

: Off (Not operated)

Setting Condition:

The low clutch duty solenoid signal is open circuit or short circuit.
(The voltage different from the output ON/OFF signals was detected while the TCM monitors the solenoid output
voltage.)

Fail Safe:

When the vehicle is running, the operation of the low clutch duty solenoid and the lock-up solenoid is stopped
(OFF), the gear position selected at the trouble detection is held, and the lock-up is inhibited.

After the vehicle stopped, all solenoid operations stop (OFF) and the gear is fixed to the 3rd.

Possible Cause:

Low clutch duty solenoid malfunction.

Open (Off) circuit or short (On) circuit harness of the low clutch duty solenoid.

Open circuit, short circuit to battery or short circuit to ground between low clutch duty solenoid terminal 3 and
TCM terminal B9 (C95).

Insufficient ground condition of the low clutch duty solenoid.

Poor connection of each connector.

DIAGNOSIS (JR405E) 7A2-59
Reference:
When the low clutch duty solenoid is operated, following signal is outputs.
Measurement terminal: B9 (C95) and B22 (C95)
-AC range by circuit tester: Approximately 6.2V
-Oscilloscope: Following wave form can be found.

Low Clutch Duty Solenoid Reference W ave Form
Measurement Terminal: B9 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: D range 4th gear
Measurement Terminal: B9 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: P, N range in idle
0V 0V

7A2 -64 DIAGNOSIS (JR405E)
DTC P1853 (Flash Code 26) Low & Reverse Brake Pressure Switch Failure



Control Valve

TCM
B1
B12
B20
RED/YEL
WHT/BLK
2-4 Brake Pressure SW
Terminal
Assembly
YEL
E54 (7)
(12)
(1)H23 (12)
(10)C95 (1)
(12)
(20)
RED/YEL
YEL
WHT/BLK
L&R Brake Pressure SW
High Clutch Pressure SWH22 (8)



Pre-setting Condition:

No gear shifting.

No Check Trans indicator lamp.

No system voltage failure.

No inhibitor switch failure.

Low & reverse brake duty solenoid 0 or 100 %.

ATF temperature more than 60 C.

ATF input voltage more than 0.1V.

Engine speed more than 500 rpm.

7A2-68 DIAGNOSIS (JR405E)
DTC P1858 (Flash Code 27) 2-4 Brake Pressure Switch Failure



Control Valve

TCM
B1
B12
B20
RED/YEL
WHT/BLK
2-4 Brake Pressure SW
Terminal
Assembly
YEL
E54 (7)
(12)
(1)H23 (12)
(10)C95 (1)
(12)
(20)
RED/YEL
YEL
WHT/BLK
L&R Brake Pressure SW
High Clutch Pressure SWH22 (8)




Pre-setting Condition:

No gear shifting.

No Check Trans indicator lamp.

No system voltage failure.

No inhibitor switch failure.

2-4 brake duty solenoid 0 or 100 %.

ATF temperature more than 60 C.

ATF input voltage more than 0.1V.

Engine speed more than 500 rpm.

DIAGNOSIS (JR405E) 7A2-69

Setting Condition:

During the running, the 2-4 brake pressure switch does not turn on though hydraulic pressure is supposed to be
generated in 2-4 brake.
(All pre-setting conditions are met for 2.5 seconds, 2-4 brake pressure switch off, high clutch pressure switch on
and gear ratio more than 0.65 or less than 0.74 with 4th gear in D range.)
Or

During the running, the 2-4 brake switch does not turn off though no hydraulic pressure is supposed to be
generated in the 2-4 brake.
(All pre-setting conditions are met for 2.5 seconds, 2-4 brake pressure switch on in D or N range.)

Fail Safe:

No fail safe function

Possible Cause:

2-4 brake duty solenoid malfunction.

2-4 brake pressure switch wire open circuit or short circuit.

Open circuit, short circuit to battery or short circuit to ground between 2-4 brake pressure switch terminal 7 and
TCM terminal B1 (C95).

2-4 brake hydraulic circuit malfunction in the control valve.

Poor connection of each connector.

Reference:
When the 2-4 brake pressure switch is operated, following signal is outputted.
Measurement terminal: B1 (C95) and B22 (C95)
-At other than 2nd or 4th gear: More than 10V
-At 2nd or 4th gear: Less than 1V

7A2-72 DIAGNOSIS (JR405E)
DTC P1863 (Flash Code 28) High Clutch Pressure Switch Failure



Control Valve

TCM
B1
B12
B20
RED/YEL
WHT/BLK
2-4 Brake Pressure SW
Terminal
Assembly
YEL
E54 (7)
(12)
(1)H23 (12)
(10)C95 (1)
(12)
(20)
RED/YEL
YEL
WHT/BLK
L&R Brake Pressure SW
High Clutch Pressure SWH22 (8)




Pre-setting Condition:

No gear shifting.

No Check Trans indicator lamp.

No system voltage failure.

No inhibitor switch failure.

2-4 brake duty solenoid 0 or 100 %.

ATF temperature more than 60 C.

ATF input voltage more than 0.1V.

Engine speed more than 500 rpm.

DIAGNOSIS (JR405E) 7A2-73

Setting Condition:

During the running, the high clutch pressure switch does not turn on though hydraulic pressure is supposed to be
generated in high clutch.
(All pre-setting conditions are met for 2.5 seconds, high clutch pressure switch off, 2-4 brake pressure switch on
and gear ratio more than 0.65 or less than 0.74 with 4th gear in D range.)
Or

During the running, the high clutch pressure switch does not turn off though no hydraulic pressure is supposed
to be generated in the high clutch.
(All pre-setting conditions are met for 2.5 seconds, high clutch pressure switch on in P, R or N range.)

Fail Safe:

No fail safe function

Possible Cause:

High clutch duty solenoid malfunction.

High clutch pressure switch open circuit or short circuit.

Open circuit, short circuit to battery or short circuit to ground of the harness between high clutch pressure switch
terminal 1 and TCM terminal B20 (C95).

High clutch hydraulic circuit malfunction in the control valve.

Poor connection of each connector.

Reference:
When the high clutch pressure switch is operated, following signal is outputted.
Measurement terminal: B20 (C95) and B22 (C95)
-At other than 3rd or 4th gear: More than 10V
-At 3rd or 4th gear: Less than 1V

7A2-74 DIAGNOSIS (JR405E)
Step Action Yes No
1 Clear the DTC from the memory once.
Was the action complete?
Go to Step 2
Refer DTC clear
method in this
manual.
2 Turn the ignition switch off once, then restart the engine and in R
range. When about 10 seconds elapsed, does the CHECK TRANS
lamp blink?
Go to Step 3 Go to Step 7
3 Is the DTC P0763 (33) High Clutch Duty Solenoid Failure stored?
Go to P0763 (33)
Section Go to Step 4
4 Connect the Tech 2 and select the item for high clutch pressure
switch. Is the indication of high clutch pressure switch turned off
when the terminal assembly connector is disconnected?
Go to Step 5
Repair the harness
or connector.
Go to Step 12
5 Turn the key switch off and disconnect the terminal assembly
connector. Are the pins correct?
Go to Step 6
Repair the
connector or pin.
Go to Step 12
6 Remove the oil pan. Is the continuity correct between terminal
assembly terminal 1 and high clutch pressure switch connector?

1

Repair the harness
or connector.
Go to Step 12
Replace pressure
switch.
Go to Step 12
7 Start the engine and shift to 4th gear in the D range. When about 10
seconds elapsed, does the CHECK TRANS lamp blink?
Go to Step 8
Go to P0763 (33)
Section
8 Connect the Tech 2, and with the key switch in OFF position, short
the terminals 11 and 1 on the vehicle harness side. Does the
indication of the high clutch pressure switch on the Tech 2 turn on
when the key switch is turned on?
Go to Step 9
Repair the harness
or connector.
Go to Step 12