Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 1858

7A2-48 DIAGNOSIS

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/RED

C95

(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 7A2-49

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/RED

C95

(6)

(7)

(8)

(9)

(22)

BLU/BLK

BLK/YEL

RED

WHT/BLU

GRY/RED

7A2-50 DIAGNOSIS

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.

DIAGNOSIS 7A2-51

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 6.8V

Low & Reverse Brake Duty Solenoid Reference Wave Form

Measurement Terminal: B6 (+)

B22 (-)

Measurement Scale: 5V/div

20ms/div

Measurement Condition: P, N range in idle

Measurement Terminal: B6 (+)

B22 (-)

Measurement Scale: 5V/div

20ms/div

Measurement Condition: R range in idle