Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 302

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-57

DTC P0727 (FLASHING CODE 13)

ENGINE REVOLUTION SIGNAL FAILURE (NE)

Step Action

Value(s)

Yes

No

1

1. Clear the TCM memory.
2. Turn the ignition "ON" and start the engine.
3. With the engine "OFF", turn the ignition

"ON".

Is DTC P0727 displayed by self-diagnosis?



Go to Step 2

DTC P0727

was

temporarily

stored into

TCM memory.

Refer to

"Diagnostic

aids".

2

1. With the engine "OFF", turn the ignition

"ON".

2. Connect a voltmeter to the TCM 28 pin

connector terminal (15) and TCM 20 pin
connector ground terminal (15 or 19).

Is the voltage within the specified value?

9-16V

Go to Step 3

Go to Step 4

3

1. With the ignition "ON" and the engine "ON".
2. Connect a voltmeter between the TCM 28

pin connector terminal (15) and TCM 20 pin
connector ground terminal (15 or 19).

Does the voltage vary in the specified value at
the engine idling?

Less than

1.4-9∼16 V

(AC intermittently)

Go to Step 5

Go to Step 6

4

Check the wiring harness between the TCM and
ECM for breaking or voltage shorted.
Was a problem found and corrected?



Go to Step 7



5

Check the TCM connection. If OK, replace the
TCM.
Is the replacement complete?



Go to Step 7



6

Check the wiring harness between the TCM and
ECM for ground shorted. If OK, the ECM or the
engine revolution sensor is faulty.
Was a problem found and corrected?



Go to Step 7



7

1. After the repair is complete, use the scan tool

to select "DTC", then "Clear Info" function.

2. Make a road running, test for the vehicle.
3. Review the scan tool "DTC Info".

Has the last test failed or is the current DTC
displayed?



Begin the
diagnosis

again.

Go to Step 1

System OK

7A-58 AUTOMATIC TRANSMISSION (AW30-40LE)

DTC P0743 (FLASHING CODE 33) TORQUE CONVERTER CLUTCH

CONTROL LOCK-UP (ON/OFF) SOLENOID FAILURE (SL)

UBS (For General Export)

D07R200062

TFR/S (For Australia) and TFR (For South Africa)

D07L200007

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-59

‘01TFR (For Thailand)

D07L200010

Circuit description:

The lock-up solenoid SL of the torque converter clutch
(TCC) controls the lock-up clutch by a signal according
to the lock-up range judgement of the TCM when the
vehicle runs.
This function can improve the fuel consumption to
almost the same extent as the manual transmission.
The lock-up solenoid SL is put into B+ by the TCM, so
that the solenoid is actuated with the result of lock-up.

Fail-safe control:

The TCM controls fail-safe by detecting SL solenoid
failure.

Failure detection:

GND SHORT detection

• When SHORT detection continues for 0.3 sec.

• When SHORT failure detection continues 8 times.

Open detection

• When OPEN detection continues for 0.5 sec.

• When OPEN failure detection continues 8 times.

Contents of control:

At failure detection

• Lock-up control inhibit

• If + B short failure is detected, keeps 1st gear when

the vehicle speed calculated by output revolution
sensor is less than 10km/h to prevent stall.
(Canceled at more than 15km/h)

At failure decision

• Executes following items in addition to above

control items at failure detection.

• Stores the failure information in failure-memory.

Conditions of turning “CHECK TRANS” lamp
off:

None

Reversion conditions from fail-safe:

When a normal condition is judged by rechecking on
the state of lock-up ON/OFF

Test description:

The following numbers correspond to the step numbers
on the diagnostic chart.
1. When the key is ON, the voltage between the TCM

20 pin connector terminals (12) and (15 or 19) is
1.0 V or less.

2. When the gear is of the 2nd speed in the D range

and the throttle opening is about 50% at a higher
speed than about 40km/h, the TCM supplies 8 to
16 V, so that the solenoid is actuated with the result
of lock-up.

3.5.7.8. The resistance range of the solenoid is 11 to

15

Ω (at 20°C).

Diagnostic aids:

In case of faulty connection, open or shorted circuit. to
the TCM 20 pin connector terminal (12), DTC P0743 is
displayed. A intermittent failure may be caused by a
poor connection, rubbed through wire insulation or a
wire broke inside the insulation.

7A-60 AUTOMATIC TRANSMISSION (AW30-40LE)

DTC P0743 (FLASHING CODE 33) TORQUE CONVERTER CLUTCH

CONTROL LOCK-UP (ON/OFF) SOLENOID FAILURE (SL)

Step Action

Value(s)

Yes

No

1

1. With the engine "OFF", turn the ignition "ON"

after warming up.

2. Connect a voltmeter between the TCM 20

pin connector terminal (12) and ground
terminal (15 or 19).

Is the voltage less than the specified value?

1 V

Go to Step 2

Go to Step 3

2

1. Lift the driving sheels and support them.
2. At the D range and 2nd speed gear.
3. Make a test at a speed of about 40 km/h or

more with 50% or more opening of the
throttle.

Is the voltage between the TCM 20 pin connector
terminal (12) and ground terminal (15 or 19)
within the specified value?

8-16V

Go to Step 4

Go to Step 5

3

1. Turn the ignition "OFF".
2. Disconnect the TCM 20 pin connector.
3. Measure the resistance between the terminal

(12) and ground.

Is the resistance within the specified value?

11-15

Ω

(at 20℃)

Go to Step 6

Go to Step 7

4

1. Clear the TCM memory.
2. Make a running test.

Is DTC P0743 displayed by self-diagnosis?



Go to Step 6

The continuity

of wiring is

intermittent.

Refer to

"Diagnostic

aids".

5

1. Turn the ignition "OFF".
2. Disconnect the TCM 20 pin connector.
3. Measure the TCM 20 pin connector terminal

(12) and ground.

Is the resistance within the specified value?

11-15

Ω

(at 20℃)

Go to Step 6

Go to Step 8

6

The TCM is faulty or the continuity of wiring
harness is intermittent.
Was a problem found and corrected?



Go to Step 12



7

Disconnect the A/T 8 pin connector.
Is the resistance between the lock-up solenoid
connector terminal (7) and ground within the
specified value?

11-15

Ω

(at 20℃)

Go to Step 9

Go to Step 10

8

Disconnect the A/T 8 pin connector.
Is the resistance between the lock-up solenoid
connector terminal (7) and ground within the
specified value?

11-15

Ω

(at 20℃)

Go to Step 11

Go to Step 10

9

Check the wiring harness between the TCM 20
pin connector terminal (12) and A/T 8 pin
connector terminal (7) for open.
Was a problem found and corrected?



Go to Step 12

