Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 373

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

Circuit Description:

The lock-up duty solenoid S3 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 S3 is put into B+ by the TCM, so
that the solenoid is actuated with the result of lock-up.

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

connector terminal (11) and ground terminal (24) is
1 V or less.

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

and the throttle opening is about 15% or more at a
higher speed than about 54 km/h (UBS), 27 km/h
(TF), 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 (20 ℃).

Diagnostic Aids:

In case of faulty connection , open or shorted circuit to
the TCM terminal (11), code 33 is displayed.
A intermittent failure may be caused by a poor
connection, rubbed through wire insulation or a wire
broken inside the insulation.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-41

CODE 33 LOCK-UP SOLENOID S3 (OPEN/SHORTED CIRCUIT)

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 26

pin connector terminal (11) and ground
terminal (24).

Is the voltage less than the specified value?

1 V

Go to Step 2

Go to Step 3

2

1. Lift the driving wheels and support them.
2. D range, 2nd speed gear.
3. Make a test at a speed of about 54 km/h

(UBS), 27 km/h (TF) or more with 15% or
more opening of the throttle.

4. Measure the voltage between the TCM 26

pin connector terminal (11) and ground
terminal (24).

Is the voltage within the specified value?

8−16 V

Go to Step 4

Go to Step 5

3

1. Turn the ignition “OFF”.
2. Disconnect the TCM 26 pin connector.
3. Measure the resistance between the terminal

(11) and ground.

Is the resistance within the specified value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 6

Go to Step 7

4

1. Clear the TCM memory.
2. Make a running test.
Is code 33 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 26 pin connector.
3. Measure the resistance between the terminal

(11) and ground.

Is the resistance within the specified value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 6

Go to Step 8

6

The TCM is faulty or the continuity of wiring is
intermittent. Refer to “Diagnostic Aids”.
Was a problem found and corrected?

−

Go to Step 12

−

7

Disconnect the A/T 12 pin connector.
Is the resistance between the solenoid S3
terminal (12) and ground within the specified
value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 9

Go to Step 10

8

Disconnect the A/T 12 pin connector.
Is the resistance between the solenoid S3
terminal (12) and ground within the specified
value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 11

Go to Step 10

9

Check the wiring harness between the TCM 26
pin connector terminal (11) and A/T 12 pin
connector terminal (12) for open.
Was a problem found and corrected?

−

Go to Step 12

−

10

Replace the lock-up solenoid S3.
Is the replacement complete?

−

Go to Step 12

−

11

Check the wiring harness between the TCM 26
pin connector terminal (11) and A/T 12 pin
connector terminal (12) for ground shorted.
Was a problem found and corrected?

−

Go to Step 12

−

7A-42 AUTOMATIC TRANSMISSION (AW30-40LE)

CODE 33 LOCK-UP SOLENOID S3 (OPEN/SHORTED CIRCUIT) (Cont’d)

Step Action

Value(s)

Yes

No

12

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

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-43

WIRING DIAGRAM

UBS

D07R200021