Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 1873

7A2-108 DIAGNOSIS

No. B10: Brake is Applied in R Range

Description:

•

Brake is applied suddenly in R range.

Diagnosis Hints:

•

Basically a trouble in the AT main unit. However, some trouble in the sensor system or output system may have

some influence on the trouble in the main unit and therefore these systems should be also checked to prevent

reproduce of the trouble.

Possible Cause:

•

Seized clutch (low clutch, high clutch, 2-4 brake).

•

Shortage or faulty quality of ATF.

•

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

•

Disordered select cable (select indicator light indicates R but the hydraulic system is not in the R range).

•

Malfunction of parking mechanism.

No. B11: Insufficient Starting or Shaking in D Range

Description:

•

Insufficient starting or shaking in D range.

Possible Cause:

•

Slip of clutch (low clutch, low one-way clutch, reverse clutch, low & reverse brake).

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

•

Shortage or faulty quality of ATF.

•

Dropped line pressure.

•

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

No. B12: Noise or Vibration is Generated at Starting

Description:

•

Noise or vibration is generated in the vicinity of AT at starting.

Diagnosis Hints:

•

Cause other than AT can be also considered. It is effective means to reproduce a running condition using a lift

up, chassis dynamo, etc. to investigate the origin (generating condition) of noise and vibration.

Caution:

Lifting up some unit to test it accompanies danger. Provide safety measures as far as possible and

carry out the test with sufficient care.

Possible Cause:

Following sources of noise or vibration other than the AT can be considered.

•

Noise from differential gears.

•

Noise from propeller shaft.

•

The bearing support in the middle of the propeller shaft has fatigued, and the bend angle of the propeller shaft

has changed, causing vibration at the time of start.

•

Unbalanced and poor uniformity of tires cause vibration.

DIAGNOSIS 7A2-109

No. C1: Engine Race Up (Slip) When Gear is Shifted Up to 1st to

2nd

No. C2: Engine Race Up (Slip) When Gear is Shifted Up to 2nd to

3rd

No. C3: Engine Race Up (slip) When Gear is Shifted Up to 3rd to

4th

No. C4: Engine Race Up (Slip) When Gear is Shift Down or Kick-

down to 4th to 3rd

No. C5: Engine Race Up (Slip) When Gear is Shift Down or Kick-

down to 4th to 2nd

No. C6: Engine Race Up (Slip) When Gear is Shift Down or Kick-

down to 3rd to 2nd

No. C7: Engine Race Up (Slip) When Gear is Shift Down or Kick-

down to 4th or 3rd to 1st

No. C8: Engine Race Up (Slip) Others

Description:

•

The engine speed up when the accelerator pedal is stepped on for acceleration and the gear is shifted up.

•

The engine speed up when the accelerator pedal is stepped on for acceleration and the gear is shifted down or

for kick-down during steady run.

•

The engine speed up when the accelerator pedal is stepped on for acceleration and the gear is shifted down or

for kick-down during steady run.

Diagnosis Hints:

•

Possibility of slip of clutch is supposed. If slip of clutch has occurred, a DTC of "Gear ratio error" is stored.

Possible Cause:

•

Slip

of

clutch.

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

•

Dropped line pressure.

•

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

7A2-110 DIAGNOSIS

Step

Action

Yes

No

1

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 2

Go to Step 2

2

Are any DTCs stored?

Go to DTC Chart

Go to Step 3

3

Are the quantity, contamination and smell normal?

If the ATF level is

low, replenish up to

the specified level.

Go to Step 4

If ATF is extremely

black and

contaminated and

smells burnt, slip of

the clutch is

supposed.

Overhaul the AT

unit.

4

Are the engine speed and other engine system correct?

Go to Step 5

Repair the defect or

replace.

5

Inspection of electrical or mechanical fault
Is the signal from each pressure switch changed synchronously?

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 SW

H22

(8)

Range

TCM terminal

Gear

B20

(High clutch

pressure SW)

B1

(2-4 brake pressure

SW)

B12 (Low & reverse

brake pressure SW)

P

-

More than 10V

More than 10V

More than 10V

R

Reverse

More than 10V

More than 10V

-

N

-

More than 10V

More than 10V

More than 10V

D, 3, 2

1st

More than 10V

More than 10V

More than 10V

2nd

More than 10V

-

More than 10V

3rd

-

More than 10V

More than 10V

4th

-

-

More than 10V

L

1st

More than 10V

More than 10V

-

2nd

More than 10V

-

More than 10V

3rd

-

More than 10V

More than 10V

4th

-

-

More than 10V

Go to Step 6

Repair the defect or

replace.

DIAGNOSIS 7A2-111

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?

TPS

TCM

A16

C56
(28)

C94
(16)

RED/WHT

C56
(49)

(38)

(57)

(69)

ECM

A47 (GND)

A35 (Output)
A26
A55 (+5V)

A69 (Idle 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 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.