Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 628

7A1–12 AUTOMATIC TRANSMISSION (4L30-E)

BACKUP MODE

If a major system failure occurs which could affect safety or damage the transmission under normal
vehicle operation, the diagnostic system detects the fault and overrides the TCM.
The “CHECK TRANS” light flashes to alert the driver, and the transmission must be manually shifted
as follows:

Select lever position

Gear Ratio Selected

D

4 (Fourth)

Manual 3

4 (Fourth)

Manual 2

3 (Third)

Manual L

1 (First)

R

Reverse

Shifts are firmer to prevent clutch slip and consequent wear. The fault should be corrected as soon as
possible.

AUTOMATIC TRANSMISSION (4L30-E) 7A1–13

FUNCTIONS OF INPUT/OUTPUT COMPONENTS

Components

Function

Speed sensor

Senses rotation of output shaft and feeds the data to Transmission

(fixed to transmission T/M) Control Module (TCM)

Throttle

Senses the extent of throttle valve opening and the speed of the throttle

position sensor (TPS)

valve lever motion to open the valve and feeds the data to TCM (fed to

(fixed to engine)

Engine Control Module (ECM) also)

Brake Switch (SW)

Senses whether the driver has pressed the brake pedal or not and feeds

(fixed to brake pedal)

the information to TCM

Kick-down SW (fixed to

Senses whether the driver has pushed the accelerator pedal fully or not

accelerator pedal)

and feeds the information to TCM

Mode SW (fixed to T/M)

Senses the select lever position and feeds the information to TCM

Power drive SW

Senses whether the driver has selected the power mode and feeds the 

(fixed to front console)

information to TCM

T/M oil temp. sensor

Senses the T/M oil temperature and feeds the data to TCM

Engine coolant 

Senses the engine cooling water temperature and feeds the data to TCM

temperature SW

(feeds the signal from ECM)

Engine speed signal

Feeds the signals monitoring engine speed to TCM from crank angle sensor
(feeds the signal from ECM)

Air conditioning

Senses whether the air conditioner has been switched on or not and

information

feeds the information to TCM

On-board diagnostic input

By monitoring the Ground (GND), the location of failure is shown on the
T/M monitor lamp (“CHECK TRANS”) by flashing the diagnostic trouble
code

Shift solenoid A, B

Selects shift point and gear position suited to the vehicle running con-
dition on the basis of TCM output

Band apply solenoid

Controls oil flow suited to the vehicle running condition on the basis of
TCM output

Torque Converter 

Controls clutch engagement/disengagement suited to the vehicle

Clutch solenoid

running condition on the basis of TCM output

Force motor

Adjusts the oil pump delivery pressure to line pressure suited to the

(Pressure regulator

vehicle running condition on the basis TCM output

valve)

Power drive mode lamp

Informs the driver whether the vehicle is in power mode or not

T/M monitor lamp

Informs the driver of failure in the system. It also displays the self diag-

(“CHECK TRANS”)

nosis code.

Data Link Connector (DLC)

When connected with TECH2 or tester, can communicate the data for
function check, etc. (fed to ECM also). When TECH2 is not connected,
can communicate the signal for torque management with ECM.

When short-circuited with the bipolar connector, the T/M monitor lamp
displays a failure by code.

S

O

L

E

N
O

I

D

O
U

T
P

U

T

S

I

G
N

A

L

I

N

P

U

T

S

I

G
N

A

L

7A1–14 AUTOMATIC TRANSMISSION (4L30-E)

RANGE REFERENCE CHART

1-2/3-4 2-3

O/DRIVE

OVERRUN FOURTH

THIRD

REVERSE

SECOND

PRINCIPLE

BAND

RANGE

GEAR

SOL SOL

ROLLER

CLUTCH

CLUTCH

CLUTCH

CLUTCH

CLUTCH

SPRAG

ASSEMBLY

ENGINE

N.C. N.O.

CLUTCH

(OC)

(C4)

(C3)

(RC)

(C2)

ASSEMBLY

(B)

BRAKING

(OFW)

(PFW)

P-N

OFF

ON

APPLIED

NO

R

REVERSE OFF

ON

LD

APPLIED

APPLIED

LD

NO

1ST

OFF

ON

LD

APPLIED

LD

APPLIED

NO

2ND

ON

ON

LD

APPLIED

APPLIED

FW

APPLIED

YES

D

3RD

ON

OFF

LD

APPLIED

APPLIED

APPLIED

NE

YES

4TH

OFF OFF

FW

APPLIED

APPLIED

APPLIED

NE

YES

1ST

OFF

ON

LD

APPLIED

LD

APPLIED

NO

3

2ND

ON

ON

LD

APPLIED

APPLIED

FW

APPLIED

YES

3RD

ON

OFF

LD

APPLIED

APPLIED

APPLIED

NE

YES

1ST

OFF

ON

LD

APPLIED

APPLIED

LD

APPLIED

YES

2

2ND

ON

ON

LD

APPLIED

APPLIED

FW

APPLIED

YES

L

1ST

OFF

ON

LD

APPLIED

APPLIED

LD

APPLIED

YES

LD : LOCKED IN DRIVE

FW : FREEWHEELING

NE : NOT EFFECTIVE

C07RT010

AUTOMATIC TRANSMISSION (4L30-E) 7A1–15

NORMAL OPERATION OF 4L30-E
TRANSMISSION

1.

TORQUE CONVERTER CLUTCH (TCC)
APPLICATION CONDITIONS:

The TCC is normally applied in 2nd, 3rd and 4th
gears only when all of the following conditions
exist:

– The engine coolant temperature is above 70°C

(158°F).

– The brake pedal is released.
– The shift pattern requests TCC apply.

Moreover, TCC is always applied in 2nd, 3rd and
4th gears when the transmission oil temperature is
above 135°C (275°F).
This mode should be canceled at 125°C (257°F).

2.

SPECIAL SHIFT PATTERN WHEN THE
ENGINE IS COLD:

A special shift pattern is activated when the engine
coolant temperature is below 70°C (158°F). (3-4
shifts for example are delayed for small throttle
openings and will occur a few MPH higher)