2004 ISUZU TF SERIES oil level

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.

7A2-104 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.

7A2-116 DIAGNOSIS (JR405E)
When signal from the speed sensor becomes out of order, it may be judged a result of changed vehicle
speed and faulty gear shifting may be the causes.







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



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 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 3 Go to Step 3
3 Are any DTCs stored?
Go to DTC Chart Go to Step 4
4 Are the quantity, contamination and smell normal?

If the ATF level is
low, replenish up to
the specified level.

Go to Step 5
If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.

DIAGNOSIS (JR405E) 7A2-121
No. E1: No Gear Shift

Description:

Range is fixed without shifting the gear of 1st to 2nd, 2nd to 3rd, and 3rd to 4th.

Gear may be shifted or may not be shifted.

Diagnosis Hints:

Fixing at some gear speed, signal error from throttle position sensor or trouble in the AT main unit are supposed.

Possible Cause:

Slip of clutch (low clutch, high clutch and 2-4 brake).
If slip of clutch is caused, a DTC (gear ratio error) is stored.

Dropped line pressure.

Fixing at 3rd position (fail-safe activated).
Since the gear is fixed at the 3rd position because of the fail-safe function, a trouble that "No gear shift"
is resulted. In this case, the DTC is memorized.
When TCM stops operation because of faulty TCM ground, the gear is fixed at the 3rd position because
of a mechanical reason. In this case, no DTC is memorized.





Incorrect properties of throttle opening signal (serial communication) of throttle position sensor.
Throttle opening signal (serial communication) of the throttle position sensor does not change in
proportion to the throttle opening. In this case, fixing at the high or low gear results in such a trouble
that "No Gear Shift".

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

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.

7A2-124 DIAGNOSIS (JR405E)
No. E2: Only 4th gear (O/D) is Not Selectable

Description:

Gear is not shifted up from 3rd to 4th though the vehicle is accelerated.

Possible Cause:

Disordered select cable.

Disordered inhibitor switch.

ATF thermo sensor detects low oil temperature (4th gear is prohibited temperature less than 10C.).

Clogged oil passage of low clutch duty solenoid.

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

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 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 3 Go to Step 3
3 Are any DTCs stored?
Go to DTC Chart Go to Step 4
4 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.

Go to Step 5
If ATF is extremely
black and
contaminated and
smells burnt, slip of
the clutch is
supposed.
Overhaul the AT
unit.

7A2-132 DIAGNOSIS (JR405E)
No. G3: Creep Force is small

Description:

Vehicle does not move though a run range is selected on a flat road during the idling.

Diagnosis Hints:

When the creep force is small in all ranges, low engine output is considered. Another possible cause is slip of
clutch. If the creep is normal only in the R range, operation of the fail-safe function due to a trouble in the electrical
system is considered.

Possible Cause:

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

Low engine output (low idling speed, out of injection timing, lowered compression pressure, etc.).

Shortage or faulty quality of ATF.

Disconnection or short circuit of solenoid valve output.

Clogged oil passage of solenoid valve output.

Faulty ground return line in AT assembly.
If the ground return line earth is faulty, clutch pressure may decrease causing slip of the clutch.

Trouble in the torque converter system (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 Are the idling speed and other engine system normal?
Go to Step 5
Repair the defect or
replace.
5 Is the stall revolution normal in D, 3, 2 and L range? Refer
the STALL TEST section in this manual.
Go to Step 6
Repair the defect or
replace.
6 Is the line pressure normal? Refer the LINE PRESSURE
TEST section in this manual. Trouble in the AT
assembly or control
valve.
Repair the defect or
replace.

7A2-134 DIAGNOSIS (JR405E)
No. I1: No Lock-up

Description:

Lockup is not performed in spite of the lock-up area.

Diagnosis:

Lockup is not performed in spite of the lock-up area.

Monitor the signal to the lock-up solenoid while carrying out a running test.

When the output signal to the lock-up solenoid is correctly sent causing no lock-up, clogged lock-up solenoid oil
passage or malfunction of the lock-up piston may be considered.

Even the lock-up area, the output signal to the lock-up solenoid is not sent, fault of the ATF thermo sensor
controlling the lockup is considered. (Lock-up is not operated at ATF temperature less than 11C or more than
128C.)
Note:
When the lock-up piston has burnt, foreign material mixed in the oil cooler is considered. In such a
case, inspect the oil cooler circuit for clogging of the oil cooler

Possible Cause:

ATF thermo sensor detects low oil temperature (Lock-up is prohibited temperature less than 10C.).

Clogged oil passage of lock-up duty solenoid.

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

Step Action Yes No
1 Are any DTCs stored?
Go to DTC Chart Go to Step 2
2 Are the quantity, contamination and smell normal?
If the ATF level is
low, replenish up to
the specified level.

Go to Step 3

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

DIAGNOSIS (JR405E) 7A2-137
No. Z2: Mode Lamp (Power Drive or 3rd Start) Does Not Light Up
When The Power Mode or 3rd Start Mode is Turned On

Description:

The mode lamp on the instrument panel does not light up though the power mode or 3rd start mode is turned on
with the ignition switch in ON position.

Possible Cause:

Faulty mode select switch is considered.

Bulb burn out.


No. Z3: Mode Lamp (Power Drive or 3rd Start) Lights Up When
The Power Mode or 3rd Start Mode is Turned Off

Description:

The mode lamp on the instrument panel lights up though the power mode or 3rd start mode is turned off with the
ignition switch in ON position.

Possible Cause:

Faulty mode select switch is considered.


No. Z4: Oil Temperature Warning Lamp Lights up

Description:

Sometimes, the oil temperature warning lamp lights up.

Possible Cause:

When the vehicle is stuck in the mud or continues to accelerate under overload, and ATF temperature exceeds
145 C, the oil temperature warning lamp lights up.

If the oil temperature warning lamp lights up under usual service condition, following causes are considered.

ATF level has increased for some fault.
Refer to "No. Z1: Transmission overheat".

Lights up due to error of the ATF oil thermo sensor.

No. Z5: Select Lever Feeling is Faulty.

Description:

Select lever feeling is faulty.

Possible Cause:

Disordered select cable.

Disordered select lever.

Faulty Manual plate.