Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 637

7A1–48 AUTOMATIC TRANSMISSION (4L30-E)

CHECK TRANS INDICATOR

Find CHECK TRANS indicator and verify if it is:

A.

Flashing: GOTO DIAGNOSTIC CHECK.

B.

Staying on: GOTHROUGH CHECK TRANS CHECK.

C.

Is never ON when the ignition key is turned on:
GOTHROUGH CHECK TRANS CHECK

D.

Is ON during 2 to 3 seconds at ignition but OFF after:
Normal operation. No DTC or malfunction.

CHECK

TRANS

821LW003

AUTOMATIC TRANSMISSION (4L30-E) 7A1–49

DIAGNOSTIC CHECK

This test determines if the transmission itself or its
inputs or outputs connections or sensors are failing.

IF you have a scan tool TECH2:

NO: Use the CHECK TRANS Indicator diagnostic
codes GOTO FLASHING CODES.

YES:

1.

Connect the TECH2: GOTHROUGH TECH2
CONNECTION.

2.

Turn on the ignition but not the engine.

3.

Push “F2” on TECH2 to see the Diagnostic Trouble
Code (DTC):

4.

IF you have DTC?
YES: write down all code numbers and do the DTC
CHECK
NO: the DTC can not help you finding the problem.
(1) GOTHROUGH “CHECK TRANS” CHECK
(2) IF it is flashing and the flash is 0.2 seconds ON

and 0.2 seconds OFF, this means that you should
have a DTC stored. Please recheck GOTO
DIAGNOSTIC CHECK and if you find the same
problem GOTO TCM MEM-CAL REPLACEMENT.

(3) IF the CHECK TRANS indicator is not flashing

GOTO WITHOUT DTC SET.

Normal

Abnormal

ON

OFF

IGN Key ON

3 Sec. 

(Lamp check)

ON

OFF

IGN Key ON

3 Sec. 

(Lamp check)

0.2 Sec.

(2.5 Hz)

3.2 Sec.

0.2 Sec.

7A1–50 AUTOMATIC TRANSMISSION (4L30-E)

“CHECK TRANS” CHECK

1.

CASE it is ON during 2 to 3 seconds at ignition (or
when the engine is cranked) but it is OFF after. The
indicator is working normally GOTO DIAGNOSTIC
CHECK.

2.

CASE it is flashing and the flash is 0.2 seconds ON
and 0.2 seconds OFF always when ignition is on
(engine cranked or not). This means that there is a
malfunction. GOTO DIAGNOSTIC CHECK.

3.

CASE the CHECK TRANS indicator is flashing always
and the flash is 0.4 seconds ON and 0.4 second OFF.
(1) This means that the Transmission Control Module

(TCM) is in flashing code mode. This mode is only
used for service. This mode is set when the
terminal 11 of data link connector C-102 is set to
ground. To go out of this mode.

(2) Check if terminal 11 of data link connector C-102

is shorted to ground. (Voltage is about 0 volts
when there is a short to ground instead of 5
volts).

(3) Check if TCM terminal D16 has the same problem.
(4) Remove the short circuit to ground due to wiring

problems.

(5) IF problem solved: GOTO CHECK TRANS

INDICATOR.
NO: GOTO TCM MEM-CAL REPLACEMENT.

ON

OFF

IGN Key ON

3 Sec. 

(Lamp check)

ON

OFF

IGN Key ON

3 Sec. 

(Lamp check)

0.2 Sec.

(2.5 Hz)

3.2 Sec.

0.2 Sec.

Normal

Abnormal

826RV061

8

7

6

5

4

3

2

1

16

15

14

13

12

11

10

9

AUTOMATIC TRANSMISSION (4L30-E) 7A1–51

TRANSMISSION
CONTROL
MODULE 
(TCM)

CHECK TRANS
INDICATOR
CONTROL

DIAGNOSTIC

INPUT

CHECK TRANS 
(METER)

B-24

8

B-24

2

FUSE
CB-5
15A

FUSE BOX

ORN/BLU

H-26

7

D16(16)

C-95

C10(10)

C-95

YEL/BLK

11

4

5

DATA LINK
CONNECTOR
(C-102)

ORN/BLU

4.

CASE it is staying ON always when Ignition is ON.
(1) This means that connection between the Lamp

and the TCM is shorted to ground.

(2) Verify if instrument panel terminal 8 of connector

B-24 is shorted to ground.

(3) Verify if the TCM connector C-95 terminal C10 is

shorted to ground.

(4) Verify that the instrument panel terminal 2 of con-

nector B-24 is connected to battery.

(5) IF problem solved: GOTO CHECK TRANS

INDICATOR.
NO: GOTO TCM MEM-CAL REPLACEMENT.

5.

CASE it is staying OFF with the ignition ON (engine
OFF).
(1) This means that connection between the lamp

and the TCM is shorted to battery or opened.

(2) Verify if instrument panel terminal 8 of connector

B-24 is shorted to battery or open.

(3) Verify if the TCM connector C-95 terminal C10 is

shorted to battery or open.

(4) Verify that the instrument panel terminal 2 of

connector B-24 is connected to battery. If not
check the fuses and the connections voltage.

(5) IF problem solved: GOTO CHECK TRANS

INDICATOR.
NO: GOTO TCM MEM-CAL REPLACEMENT.

D07LW004