2004 ISUZU TF SERIES oil

DIAGNOSIS (JR405E) 7A2-95
No. A3: Vehicle Does Not Run in D, 3, 2 and L Range

Description:

Vehicle does not run in D, 3, 2 and L range only.

It runs correctly in R ranges.

Diagnosis Hints:

Some trouble in the AT main unit is supposed (since the vehicle can run even if the TCM is defective). However,
since the trouble of the main unit may be originated from the sensor system or output system, these systems
should be also checked to prevent reproduce of the trouble.

Possible Cause:

Slip of clutch (low clutch and low one-way clutch).
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).

Disordered select cable (select indicator light indicates D, 3, 2 and L but the hydraulic system is not in the D, 3, 2
and L range).

Faulty torque generated.

Trouble in the torque converter (faulty operation, sticking), insufficient engine output.

Malfunction of parking mechanism.

Step Action Yes No
1 Dislocation or disordered of select lever.
Does the vehicle move when the brake is released in a
position other than the P range and the vehicle is pushed?

Go to Step 2

Adjust the select cable.
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 Is the stall revolution correct in D, 3, 2 and L range? Refer
the STALL TEST section in this manual.
Go to Step 5
Repair the defect or
replace.
5 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.

7A2-96 DIAGNOSIS (JR405E)
No. B1: Vehicle Runs in N Range

Description:

Creep appears in N range.

Vehicle moves unless the brake pedal is stepped on in N 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, low one-way clutch, reverse clutch, low & reverse brake).

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

Dislocated select lever (the select indicator light indicates the N range but the hydraulic system is in the D, 3, 2
or L range).

Step Action Yes No
1 Dislocation or disordered of select lever.
Does the vehicle move when the brake is released in a
position other than the P range and the vehicle is pushed?

Go to Step 2

Adjust the select cable.
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.

Trouble in the AT
assembly or control
valve.

If ATF is extremely
black and
contaminated and
smells burnt, slip of the
clutch is supposed.
Overhaul the AT unit.

7A2-100 DIAGNOSIS (JR405E)
No. B3: Engine Race Up During Starting (Slip)

Description:

The engine speeds up but vehicle speed does not increase when the accelerator pedal is stepped on at the
starting.

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).

7A2-104 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.

DIAGNOSIS (JR405E) 7A2-105
Step Action Yes No
5 Inspection of electrical or mechanical fault
When the D range is selected from D at idling speed, is the signal
to the lock-up solenoid turned off using the Tech 2 or circuit
tester?
Control Valve

TCM
B17
B23 BLK Lock-up Solenoid

Te rm i n a l
Assembly
VIO Line Pressure Solenoid

E54
(4)
(6)H23
(14)
(6)C95
(17)
(23) BLK
VIO
TCM terminal
Lock-upB17
At lock-up Approx. 2.2 - 9.0 V (AC range)
At unlock-up Approx. 1.0 - 2.0 V (AC range)
Go to Step 6
Find a cause to turn
on the lockup
solenoid
6 Check of clogging of oil cooler
When blowing the oil cooler outlet with air, does some foreign
substance come out?
Clean or replace the
oil cooler.
Go to Step 7
Clogged lock-up
solenoid oil
passage. Faulty
operation of lock-up
piston.
Faulty control valve.
7 Is the stall revolution correct in D, 3, 2 and L range? Refer the
STALL TEST section in this manual.
Go to Step 8
Repair the defect or
replace.
8 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.

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).