2004 ISUZU TF SERIES clutch

DIAGNOSIS (JR405E) 7A2-101
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 SWH22
(8)
Range TCM terminal
GearB20
(High clutch
pressure SW)B1
(2-4 brake pressure
SW)B12 (Low & reverse
brake pressu re SW)
P - More than 10V More than 10V More than 10VR Reverse More than 10V More than 10V -N - More than 10V More than 10V More than 10VD, 3, 2 1st More than 10V More than 10V More than 10V2nd More than 10V - More than 10V3rd - More than 10V More than 10V4th - - More than 10VL 1st More than 10V More than 10V -2nd More than 10V - More than 10V3rd - More than 10V More than 10V4th - - More than 10VGo to Step 6
Repair the defect or
replace.

DIAGNOSIS (JR405E) 7A2-103
No. B4: Large Shock When Shift Lever is Changed to N to D
Range or N to R Range

Description:

Large shock is felt when selecting D or R range from N range during the idling after warming up.

Diagnosis Hints:

Check the entire condition of the vehicle for unusual other than AT including faulty engine mount, exhaust
hanger, etc.

When the fail-safe operation, select shock may grow worse. In such a case, check for the DTC. If no DTC is
issued, shock due to faulty operation of the control valve or burnt clutch is considered.

Possible Cause:

High engine idling.

Dislocated select lever, improper inhibitor switch adjusting point.

Faulty or insufficient tightening of engine mount, exhaust mount.

Play of suspension.

Burnt clutch.

Too low or high line pressure.

Faulty input signal system.

Faulty control valve. (faulty operation or sticking of accumulator)

7A2-104 DIAGNOSIS (JR405E)
No. B5: Engine Stalls When Selecting From N Range to
R, D, 3, 2 or L Range

Description:

The engine stalls when selecting from N or P range to a run range during the engine idling.

Diagnosis Hints:

As causes attributable to the engine, faulty idle up, insufficient engine output, etc. are considered.

As a cause of the AT system, faulty lockup piston system (lockup engine stall) is considered.

If the oil through resistance increases remarkably due to clogged oil cooler or some other reason, or if the ATF
level decreases, the lock-up piston works causing the engine stall.

Possible Cause:

Disordered idling speed, faulty idle up, faulty engine output, shortage output.

Insufficient ATF quantity (dropped level).

Clogged oil cooler (foreign substance mixed in).

Faulty lock-up piston (clogged oil passage of solenoid drive circuit, faulty operation).

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 Check of engine idle up speed
Does the idle speed increase when the air conditioning or other
electric load is turned on?
Go to Step 5
Repair the defect or
replace.

7A2-106 DIAGNOSIS (JR405E)
No. B6: Engine Starter Does Not Run in P or N Range
No. B7: Engine Starter Runs Except in P or N Range

Description:

The engine starter does not run though the P or N range is selected.

The engine starter runs though the R or D, 3, 2or L range is selected.

Possible Cause:

Disordered select cable.

Disordered Inhibitor switch, disconnection or short-circuit of inhibitor switch.


No. B8: Extended Time Lag When Shift Lever is Changed to N to D

Description:

The shift time lag is longer than standard value when shift lever is changed to N to D.

Possible Cause:

Forward range line pressure is low.

Slip of low & reverse clutch.

Slip of low one-way clutch.

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

Faulty low clutch duty solenoid operation.

Shortage or faulty quality of ATF.


No. B9: Extended Time Lag When Shift Lever is Changed to N to R

Description:

The shift time lag is longer than standard value when shift lever is changed to N to R.

Possible Cause:

Reverse range line pressure is low.

Slip of low & reverse brake.

Slip of reverse clutch.

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

Faulty low & reverse brake duty solenoid operation.

Shortage or faulty quality of ATF.

DIAGNOSIS (JR405E) 7A2-107
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.

7A2-108 DIAGNOSIS (JR405E)
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).

DIAGNOSIS (JR405E) 7A2-109
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 SWH22
(8)
Range TCM terminal
GearB20
(High clutch
pressure SW)B1
(2-4 brake pressure
SW)B12 (Low & reverse
brake pressu re SW)
P - More than 10V More than 10V More than 10VR Reverse More than 10V More than 10V -N - More than 10V More than 10V More than 10VD, 3, 2 1st More than 10V More than 10V More than 10V2nd More than 10V - More than 10V3rd - More than 10V More than 10V4th - - More than 10VL 1st More than 10V More than 10V -2nd More than 10V - More than 10V3rd - More than 10V More than 10V4th - - More than 10V
Go to Step 6
Repair the defect or
replace.

DIAGNOSIS (JR405E) 7A2-111
No. C9: Barking Feel When Gear is Shifted Up to 1st to 2nd
No. C10: Barking Feel When Gear is Shifted Up to 2nd to 3rd
No. C11: Barking Feel When Gear is Shifted Up to 3rd to 4th

Description:

Brake feeling appears when the accelerator pedal is stepped on for acceleration and the gear is shifted up.

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).