lock ISUZU TF SERIES 2004 Workshop Manual

DIAGNOSIS (JR405E) 7A2-45

Setting Condition:

No range signal is entered from the inhibitor switch with the engine speed over 500 rpm for 2 seconds.
Or

Multiple signals are entered from the inhibitor switch for 1 second.

Fail Safe:

When the vehicle is running, 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:

Inhibitor switch incorrect adjustment.

Inhibitor switch malfunction.

Open circuit or short circuit to battery between inhibitor switch terminal 2 and TCM terminal A2 (C94), terminal 4
and TCM terminal B19 (C95), terminal 8 and TCM terminal B10 (C95), terminal 5 and TCM terminal B11 (C95),
terminal 1 and TCM terminal A17 (C94), terminal 9 and TCM terminal B2 (B95), or terminal 6 and TCM terminal
B21 (C95), or short between respective harness.

Power supply wire open circuit or short circuit to ground between inhibitor switch terminal 3 and power supply
circuit.

Poor connection of each connector.


Reference:
Following continuity can be measured by circuit tester.

10 7 3 2 4 8 5 1 9 6
P
R
N
D
3
2
L

7A2-46 DIAGNOSIS (JR405E)
DTC P1120 (Flash Code 22) Throttle Signal Failure





TPS TCM



A16
C56 (29)C94 (16)
RED/WHT
C56
(49)

(38)
(57)
(69)

ECM







C56 (ECM-A)

Setting Condition:

No throttle signal is sent from the ECM for 0.4 seconds.

Fail Safe:

When the vehicle is running, 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:

Throttle position sensor malfunction.

Signal wire open circuit or short circuit to battery of the harness between ECM 29 (C56) and TCM terminal A16
(C94).

Poor connection of each connector.

Reference:

At throttle position 0%, OFF duty signal 10% is sent from ECM terminal 29 (C56) to TCM terminal A16 (C94).

At throttle position 100% (WOT), OFF duty signal 90% is sent from ECM terminal 29 (C56) to TCM terminal A16
(C94).

7.14ms 7.14ms


Time Time
0.714ms 6.426ms
Vo l t a ge
Off duty 10% =Throttle Position 0%
Vo l t a ge
Off duty 90% =Throttle Position 100%

DIAGNOSIS (JR405E) 7A2-47
DTC P1875 (Flash Code 25) GND Return Circuit Failure
Control Valve



TCM

B6




B7



B8



B9


B22 (GND)
BLU/BLK
WHT/BLU
L&R Brake Solenoid

Terminal
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



Setting Condition:

Ground return circuit is failed 7 times continuously after the low & reverse brake duty solenoid output signal turn
on.

Fail Safe:

All solenoid operations are stopped (OFF), the gear is fixed to the 3rd, and the lock-up is inhibited. (In case of
fail-safe valve failure, gear shift to 4th (over-drive) and lock-up are inhibited.)

Possible Cause:

Ground return wire open circuit between terminal assembly terminal 11 and TCM terminal B22 (C95).

Poor connection of each connector.

DIAGNOSIS (JR405E) 7A2-49
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 & reverse brake 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 & reverse brake 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 & reverse brake duty solenoid malfunction.

Open (Off) circuit or short (On) circuit harness of the low & reverse brake duty solenoid.

Open circuit, short circuit to battery or short circuit to ground between low & reverse brake duty solenoid terminal
5 and TCM terminal B6 (C96).

Insufficient ground condition of the low & reverse brake duty solenoid.

Poor connection of each connector.

7A2-52 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 2-4 brake 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 2-4 brake 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:

2-4 brake duty solenoid malfunction.

Open (Off) circuit or short (On) circuit of the 2-4 brake duty solenoid.

Open circuit, short circuit to battery or short circuit to ground of the harness between 2-4 brake duty solenoid
terminal 9 and TCM terminal B7 (C95).

Insufficient ground condition of the 2-4 brake duty solenoid.

Poor connection of each connector.

DIAGNOSIS (JR405E) 7A2-55
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 high 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 high 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:

High clutch duty solenoid malfunction.

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

Open circuit, short circuit to battery or short circuit to ground between high clutch duty solenoid terminal 10 and
TCM terminal B8 (C95).

Insufficient ground condition of the high clutch duty solenoid.

Poor connection of each connector.

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.

7A2-60 DIAGNOSIS (JR405E)
DTC P0748 (Flash Code 35) Line Pressure Solenoid Failure

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


Setting Condition:

The line pressure 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:

The operation of the line pressure solenoid is stopped (OFF).

Possible Cause:

Line pressure solenoid malfunction.

Line pressure solenoid harness open (Off) circuit or short (On) circuit.

Open circuit, short circuit to battery or short circuit to ground between line pressure solenoid terminal 6 and TCM
terminal B23 (C95).

Insufficient ground condition of the line pressure solenoid.

Poor connection of each connector.

7A2-62 DIAGNOSIS (JR405E)
DTC P1860 (Flash Code 36) Lock-up Duty Solenoid Failure

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


Setting Condition:

The lock-up 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:

The lock-up is inhibited.

Possible Cause:

Lock-up duty solenoid malfunction.

Open (Off) circuit or short (On) circuit of the lock-up duty solenoid.

Open circuit, short circuit to battery or short circuit to ground between lock-up duty solenoid terminal 4 and TCM
terminal B17 (C95).

Insufficient ground condition of the lock-up duty solenoid.

Poor connection of each connector.

DIAGNOSIS (JR405E) 7A2-63

Reference:
When the lock-up duty solenoid is operated, following signal is outputted.
Measurement terminal: B17 (C95) and B5 (C95)
-AC range by circuit tester: Approximately 2.2 – 9.0V at Lock-up / Approximately 1.0 – 2.0 V at Unlock-up
-Oscilloscope: Following wave form can be found.


Lock-up Duty Solenoid Reference Wave Form
Measurement Terminal: B17 (+) B5 (-)
Measurement Scale: 10V/div 5ms/div
Measurement Condition: Lock-up condition
0V


Lock-up Duty Solenoid Reference Wave Form
Measurement Terminal: B17 (+) B5 (-)
Measurement Scale: 10V/div 5ms/div
Measurement Condition: Unlock-up condition
0V