Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 371

7A-32 AUTOMATIC TRANSMISSION (AW30-40LE)

CODE 24 VEHICLE SPEED SENSOR 1 (OPEN/SHORTED CIRCUIT)

Step Action

Value(s)

Yes

No

1

1. Lift the driving wheels.
2. With engine idling in gear and D range.
Is the Tech 2 displayed speed the specified
value?

0 km/h

Go to Step 2

Code 24 is

intermittent.

If other codes

are not stored,

refer to

“Diagnostic

Aids”.

2

Does the speedometer operate?

−

Go to Step 3

Go to Step 4

3

1. Open the throttle and increase the revolution

speed of the driving wheels.

2. Measure the voltage between the TCM 26

pin connector terminal (6) and ground
terminal (24) with a voltmeter.

Does the voltage vary intermittently in the
specified value?

Less than 1.4−

About 5 V

(Vehicle speed 10

−20 km/h)

Go to Step 5

Go to Step 6

4

The vehicle speed sensor 1 or the speed meter
is faulty.
Was a problem found and corrected?

−

Go to Step 7

−

5

The TCM connection is faulty or the TCM is
faulty.
Was a problem found and corrected?

−

Go to Step 7

−

6

The wiring harness between the speed meter
and TCM is open or the vehicle speed sensor 1
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

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-33

CODE 31 SHIFT SOLENOID S1 (OPEN/SHORTED CIRCUIT)

UBS

D07R200026

TF

D07R200018

Circuit Description:

The shift solenoid S1 changes the hydraulic route with
the signals from the TCM according to the vehicle
speed and the throttle opening to control shifting. When
the solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.

Test Description:

The following numbers correspond to the step numbers
on the diagnostic chart.
1. With the key “ON”, the voltage between the TCM

terminal (13) and ground terminal (24) is 8 to 16 V.

4. When the driving wheels revolve with the 3rd

speed gear, the voltage is 1 V or less.

3. 6. 8. 11. The solenoid resistance is within the range

of 11 to 15 Ω (20 ℃).

Diagnostic Aids:

In case of faulty connection , open or shorted circuit to
the TCM terminal (13), code 31 is displayed.
A intermittent failure may be caused by a poor
connection, rubbed through wire insulation or a wire
broken inside the insulation.

7A-34 AUTOMATIC TRANSMISSION (AW30-40LE)

CODE 31 SHIFT SOLENOID S1 (OPEN/SHORTED CIRCUIT)

Step Action

Value(s)

Yes

No

1

1. With the engine “OFF”, turn the ignition

“ON”.

2. Connect a voltmeter between the TCM 26

pin connector terminal (13) and ground
terminal (24).

Is the voltage within the specified value?

8−16 V

Go to Step 2

Go to Step 3

2

1. Lift the driving wheels.
2. Turn the ignition “ON”, engine “ON”.
Can the speed be changed normally by
acceleration in the “NORMAL” mode and the D
range?

−

Go to Step 4

Go to Step 8

3

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

(13) and ground.

Is the resistance within the specified value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 5

Go to Step 6

4

At the 3rd speed.
Is the voltage between the TCM 26 pin connector
terminal (13) and ground terminal (24) less than
the specified value?

1 V

Go to Step 7

Go to Step 8

5

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

−

Go to Step 13

−

6

Disconnect the A/T 12 pin connector.
Is the resistance between the solenoid S1
terminal (1) and ground within the specified
value.

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 9

Go to Step 10

7

1. Clear the TCM memory.
2. Make a running test.
Is code 31 displayed by self-diagnosis?

−

Go to Step 5

The continuity

of wiring is

intermittent.

Refer to

“Diagnostic

Aids”.

8

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

(13) and ground.

Is the resistance within the specified value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 5

Go to Step 11

9

Check the wiring harness between the TCM 26
pin connector terminal (13) and A/T 12 pin
connector terminal (1) for ground shorted.
Was a problem found and corrected?

−

Go to Step 13

−

10

Replace the shift solenoid S1.
Is the replacement complete?

−

Go to Step 13

−

11

1. Disconnect the A/T 12 pin connector.
2. Measure the resistance between the terminal

(1) and ground.

Is the resistance within the specified value?

11−15 Ω (20 ℃)
12−16 Ω (40 ℃)

Go to Step 12

Go to Step 10

12

Check the wiring harness between the TCM 26
pin connector terminal (13) and A/T 12 pin
connector terminal (1).
Was a problem found and corrected?

−

Go to Step 13

−

AUTOMATIC TRANSMISSION (AW30-40LE) 7A-35

CODE 31 SHIFT SOLENOID S1 (OPEN/SHORTED CIRCUIT) (Cont’d)

Step Action

Value(s)

Yes

No

13

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