brake ISUZU TF SERIES 2004 Workshop Manual

DIAGNOSIS (JR405E) 7A2-35
FAIL-SAFEFUNCTION
Fail-Safe Condition
Flash Code
(P-Code)

Description
CHECK
TRANS
Warning

Gear Shift
Solenoid
Line
Pressure
Solenoid

Lock-up

Remark
11
(P0722)
Vehicle peed Sensor No
Signal ON 3rdFix All Stop - Inhibited
13
(P0727)
Engine Revolution Sensor
No Signal ON - - - Inhibited
14
(P0717)
Turbine Speed Sensor No
Signal ON 3rdFix All Stop - Inhibited
15
(P0710)
ATF Temperature Sensor
Failure OFF 3,2,L - - Inhibited*1
16
(P0560)
System Voltage Failure ON 3rdFix All Stop - Inhibited*2
17
(P0705)
Inhibitor Switch Failure ON 3rdFix All Stop - Inhibited
22
(P1120)
Throttle Signal Failure ON 3rdFix All Stop - Inhibited
25
(P1875)
GND Return Circuit
Failure ON 3rdFix All Stop - Inhibited*2
26
(P1853)
Low & Reverse Brake
Pressure Switch Failure ON No Fail-safe Function
27
(P1858)
2-4 Brake Pressure
Switch Failure ON No Fail-safe Function
28
(P1863)
High Clutch Pressure
Switch Failure ON No Fail-safe Function
31
(P0753)
Low & Reverse Brake
Duty Solenoid Failure ON 3rdFix All Stop - Inhibited
32
(P0758)
2-4 Brake Duty Solenoid
Failure ON 3rdFix All Stop - Inhibited
33
(P0763)
High Clutch Duty Solenoid
Failure ON 3rdFix All Stop - Inhibited
34
(P0768)
Low Clutch Duty Solenoid
Failure ON 3rdFix All Stop - Inhibited
35
(P0748)
Line Pressure Solenoid
Failure ON - - Stop -
36
(P1860)
Lock-up Duty Solenoid
Failure ON - - - Inhibited
41
(P0731)
1stGearRatioError ON No Fail-safe Function
42
(P0732)
2ndGearRatioError ON No Fail-safe Function
43
(P0733)
3rdGearRatioError ON No Fail-safe Function
44
(P0734)
4thGearRatioError ON No Fail-safe Function
51
(P1750)
Low & Reverse Brake
Fail-safe Valve Failure ON 3rdFix All Stop - Inhibited
52
(P1755)
2-4 Brake Fail-safe Valve
Failure ON 3rdFix All Stop - Inhibited
-
(P0602)
ECU Programming Error ON No Fail-safe Function
*1: When the engine speed is more than 470 rpm for 10 minuets, the lock-up and gear shift to 4th (over-drive) are
allowed.
*2: In case of fail-safe valve failure, gear shift to 4th (over-drive) is inhibited.

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.

7A2-48 DIAGNOSIS (JR405E)
DTC P0753 (Flash Code 31) Low & Reverse Brake Duty Solenoid 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

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.

7A2-50 DIAGNOSIS (JR405E)
Reference:
When the low & reverse brake solenoid is operated, following signal is outputted.
Measurement terminal: B6 (C95) and B22 (C95)
-AC range by circuit tester: Approximately 6.2V
-Oscilloscope: Following wave form can be found.

Low & Reverse Brake Duty Solenoid Reference Wave Form
Measurement Terminal: B6 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: P, N range in idle
Measurement Terminal: B6 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: R range in idle
0V
0V

DIAGNOSIS (JR405E) 7A2-51
DTC P0758 (Flash Code 32) 2-4 Brake 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

7A2-52 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) 7A2-53
Reference:
When the 2-4 brake duty solenoid is operated, following signal is outputted.
Measurement terminal: B7 (C95) and B22 (C95)
-AC range by circuit tester: Approximately 6.2V
-Oscilloscope: Following wave form can be found.


2-4 Brake Duty Solenoid Reference Wave Form
Measurement Terminal: B7 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: P, N range in idle
Measurement Terminal: B7 (+) B22 (-)
Measurement Scale: 5V/div 10ms/div
Measurement Condition: D range 4th gear
0V 0V

7A2-54 DIAGNOSIS (JR405E)
DTC P0763 (Flash Code 33) High 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

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.