Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 656

7A1–124 AUTOMATIC TRANSMISSION (4L30-E)

DIAGNOSTIC TROUBLE CODE (DTC) 61

GEAR ERROR

This DTC flashes the CHECK TRANS indicator and
sets the BACKUP MODE.

Circuit Description:

•

The Transmission Control Module (TCM) is
calculating the slippage of the Converter and
transmission based upon the Engine Speed, the
Output Speed and the current gear ratio.

•

The slippage of the converter at a high enough
engine speed is low. Then the transmission
should not slip more than a given value when
there is no shift.

Diagnostic Aids:

•

This Diagnostic is not an electrical test done by
the TCM but a test between different information
(“logic test”).

•

Detection conditions:
1 Engine Speed > 3500 RPM
2 Using the ratio of the current gear the

Converter Slippage is calculated based upon
the engine speed and the output speed. This
slippage must be more than:
528 RPM in 4th gear
536 RPM in 3rd gear
556 RPM in 2nd gear
595 RPM in 1st gear

3 No malfunction: Engine Speed (DTC 13).

Output Speed (DTC 11). Downshift Protection
(DTC 62).

4 The last change of shift solenoid was more

than 3 seconds ago.

5 The conditions need to be present for at least

5.5 seconds.

•

Action after the detection time: BACKUP MODE.

•

Recovery conditions: To recover, do an IGNITION
CYCLE.

NOTE:
The TCC slip data is a calculated value, and not an
accurate one.
This value should be used to see if the TCC is
engaged or not.

AUTOMATIC TRANSMISSION (4L30-E) 7A1–125

DIAGNOSTIC TROUBLE CODE (DTC) 61

GEAR ERROR

IF the car has been in BACKUP MODE when the problem
occurred:

YES

IF there is another DTC which causes Backup Mode
(DTC20, DTC21, DTC22, DTC23, DTC25, DTC26, DTC31,
DTC32, DTC34, DTC35, DTC36, DTC37, DTC41, DTC42,
DTC44, DTC46, DTC54, DTC63, DTC82):

YES

Verify this other diagnosis first (because,
in backup mode the DTC61 is detected in
Manual 2 at high engine speed though
there is no problem). GOTO next DTCs.

NO

IF there is other DTC:

YES

Do a test drive to reproduce the
problem using the DRIVER
INFORMATION.

NO

GOTO next DTCs.

IF reproduced without Backup
Mode:
GOTO TCM MEM-CAL
REPLACEMENT.

NO

7A1–126 AUTOMATIC TRANSMISSION (4L30-E)

DIAGNOSTIC TROUBLE CODE (DTC) 62

DOWNSHIFT PROTECTION

This DTC flashes the CHECK TRANS indicator and
sets the BACKUP MODE.

Circuit Description:

•

The output speed information is used to
determine if the transmission has to upshift or
downshift.

•

If this information suddenly changes due to an
open circuit or some electrical interference the
transmission would downshift. 

•

To avoid this the Transmission Control Module
(TCM) is constantly checking the variations of the
Output Speed. If this variation is too great (too
much decrease or increase) DTC62 is set. This
variation is taken into amount only when the
output speed is more than 2900 RPM (approx. 90
KPH).

•

The transmission output speed sensor provides
information on vehicle speed to the TCM. The
speed sensor circuit consists of a magnetic
induction type sensor. The sensor is mounted
above a target wheel pressed on the output shaft
in the transmission extension. As the output shaft
turns, the target wheel teeth induce a variable

voltage in the magnetic pickup. This alternating
current (AC) signal is provided to the TCM. The
voltage increases with the speed of the wheel but
this is not used to define the speed of the vehicle.
As the vehicle moves faster, the signal alternates
faster between positive and negative voltages.
The Output speed information is proportional to
the frequency of the signal.

Diagnostic Aids:

•

This Diagnostic is not an electrical test done by
the TCM but a test between different information
(“logic test”).

•

Detection conditions:
1 Variation of Output Speed >512 RPM (approx.

16 KPH)/0.025s.

2 Ignition ON more than 5 seconds.
3 Mode Switch not in P, N or R.
4 Last Output Speed > 2900 RPM.
5 The conditions need to be present for at least

0.1 second.

•

Action after the detection time: BACKUP MODE.

•

Recovery conditions: To recover, do an IGNITION
CYCLE.

TRANSMISSION
CONTROL
MODULE (TCM)

TRANSMISSION
SPEED SENSOR

A12(12)

C-96

C-95

C1(1)

D1(17)

1

M-15

2

TRANSMISSION SPEED 
SENSOR SHIELDS

+

—

OUTPUT
SPEED
INPUT

H-23

10

11

9

PNK

B11(23)

B12(24)

GROUND

BLK

BLK

7

H-25

PNK

BLU

BLK

BLU

D07LW006

AUTOMATIC TRANSMISSION (4L30-E) 7A1–127

DIAGNOSTIC TROUBLE CODE (DTC) 62

DOWNSHIFT PROTECTION

If the DTC 53 is set:

CAUTION:

If wire to connector C-96 terminal B12 is short to voltage,
Transmission Control Module (TCM) will be damaged.

YES

GOTHROUGH DTC53 first and do a test drive.

NO

If you have a SCAN TOOL: TECH2?

YES

•

Raise drive wheels.

•

Connect the TECH2 GOTHROUGH TECH2
CONNECTION.

•

Push F0: DATA LIST: DISPLAY. Read “AT
OUTPUT SPEED”.

IF: Output speed different from 0 RPM when the
wheels are turning:

NO

YES

NO

Problem is intermittent.
GOTO INTERMITTENT
CONDITIONS.

GOTO DTC 11: OUTPUT SPEED
FAILURE:
Diagnostic Aids.

•

Ignition switch OFF.

•

Disconnect TCM connector C-95 and C-96.

•

Connect ohmmeter between connector C-96 terminals A12 and B12.

IF: Display is approx. 3K ohms:

NO

•

Disconnect transmission speed sensor
connector M-15.

•

Connect ohmmeter between terminals 1 and
2 of the speed sensor.

IF: Display approx. 3K ohms:

•

Connect ohmmeter between connector C-96 terminal
A12 and ground connector C-95 terminal C1.

IF: Display indicates an open circuit:

YES

•

Wires from connector
C-96 to sensor
connector are open or
shorted together.

•

Repair.

Replace
transmission
speed sensor.

NO

YES

NO

YES

•

Check for faulty TCM
connection. If OK
GOTO TCM MEM-CAL
REPLACEMENT.

A

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