ECO mode ISUZU AXIOM 2002 Service Owner's Manual

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±88
StepActionYe sNo
11. Turn on the starter switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the TOD (or 2H) position, is
12V observed between terminals 44 and 47 (4L switch)?
Go to Step 2Go to Step 4
21. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the 4L position, does the
transfer become the 4L state?
Go to Step 3
Refer to
ªDiagnosis from
symptomº.
3Is 0V observed between the terminal 44 and 47?The ECU has
failed.Replace
the ECU.
Go to
Step 10Go to Step 10
41. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the TOD (or 2H) position, is
12V observed between the connector (C±37) terminal 22 and 25?
Go to Step 5Go to Step 6
51. Turn off the starter switch and connect the EUC connector.
2. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the 4L position, is 0V
observed between terminals (C±37) 22 and (C±37) 25 (4L
switch)?The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 6
61. Turn off the starter switch and connect ECU connector.
2. Turn on the starter switch.
3. The car stops, the AT selector is the N position, and the brake
is applied.
4. Change the TOD switch to the TOD (or 2H) position.
5. After the transfer has changed to the TOD (or 2H) mode, turn
off the starter switch and disconnect the ECU connector
(C±37).
Is there the continuity between the connector (C±37) terminal 22
and 25?
Go to Step 9Go to Step 7
71. Turn off the starter switch and connect the ECU connector.
2. Turn on the starter switch.
3. The car stops, the AT selector is the N position, and the brake
is applied.
4. Change the TOD switch to the 4L position.
5. After the transfer has changed to the 4L mode, turn off the
starter switch.
6. Disconnect the ECU connector.
Is there the continuity between the connector (C±37) terminal 22
and 25?
The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 8
81. Turn off the starter switch and connect the ECU connector.
2. Turn on the starter switch.
3. The car stops, the AT selector is the N position, and the brake
is applied.
4. Change the TOD switch to the TOD (or 2H) position.
5. After the transfer has changed to the TOD (or 2H) mode, turn
off the starter switch.
6. Disconnect the transfer connector (A±1).
Is there the continuity between the connector terminal (A±1) 12
and GND?
Repair the
transfer.
Go to
Step 10
Repair the circuit
between (C±37)
22 and (A±1) 12.
Go to
Step 10

4B2±95
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
1Start the engine.
When the TOD switch is selected to the TOD position, is 0V
observed between terminals 42 and 47?
Go to Step 2Go to Step 4
21. The car stops, the AT selector is N position, and the brake is
applied.
2. Select the TOD switch to the 4L position.
Is 0V observed between terminals 42 and 47?
Go to Step 3Go to Step 4
31. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 12V
observed between the terminal 19 and 47?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
The ECU has
failed.Replace
the ECU.
Go to
Step 8
41. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 2H position, is the battery
voltage observed between the terminal 23 and 47.
Go to Step 5Go to Step 7
5When the TOD switch is selected to the TOD position (TOD
mode), is 0 ~ 1V observed between terminals 23 and 47?
Go to Step 6Go to Step 7
61. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 0V
observed between terminals 23 and 47?Repair the circuit
or check the
ªFront Axle
Disconnectº.
(Refer to
section
4B
)
Go to
Step 8Go to Step 7
7Is any of the trouble codes 28 (P1760), 32 (P1761) and 33
(P1762) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.The ECU has
failed. Replace
the ECU.
Go to
Step 8
8Check that all the parts are mounted.
Is this step complete?
Verify the repair.Go to Step 8

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±102
Diagnosis from Symptom
Troubles that are not indicated by the warning lamp are
listed in the table below. These troubles are caused by the
faults that cannot be detected by the self-diagnostic
function of the control unit.
If this type of trouble is observed, interview the customer
and conduct test runs to reproduce the trouble,
cross-check the reported trouble with the listed
phenomena, and diagnose and analyze the trouble on the
item by item basis.
PhenomenaMajor causeCorrective action
1The tight corner braking is
observed when the vehicle is
subject to full steering.
The standard tires are not used.

The tire pressure is incorrect.

The tires are worn inuniformity.

The transfer or wiring is
imperfect.

The limited slip differential is
failed.Check and recondition the
vehicle according to Chart 1.
2Even if the TOD switch is selected
to the TOD position, the F4WD
mode is not active, resulting in
remarkable rear wheel spin.
The transfer or wiring is
imperfect.

The shift on the fly system is
failed.Check and recondition the
vehicle according to Chart 2.
3
When the TOD switch is
selected to the TOD position,
the drive resistance of the
F4WD system is too large to get
sufficient running speed.

Noised drive line.
The standard tires are not used.

The tires are worn inuniformity.

The transfer or wiring is
imperfect.

The limited slip differential is
failed. Check and recondition the
vehicle according to Chart 1.
4The shift on the fly system (front
axle disconnect) generates gear
noises.
The wiring is imperfect.

The shift on the fly system is
failed.Check and recondition the
vehicle according to Chart 3.
5The braking distance gets long
even when the ABS is active.
The wiring is imperfect.

The ABS is failed.Check and recondition the
vehicle according to Chart 4.
6The transfer does not change to the
low range from the high range.
The transfer or wiring is
imperfect.

The TOD switch is imperfect.

The AT inhibitor switch is
imperfect.
Check and recondition the
vehicle according to chart 5.
7The transfer does not change to the
high range from the low range.
im erfect.

The brake switch is imperfect.

The engine speed signal is
imperfect.

The speed sensor is imperfect.
Check and recondition the
vehicle according to chart 6.
8The transfer stays neutral and the
vehicle does not run.
The transfer is imperfect.Check and recondition the
vehicle according to chart 7.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±108
Chart 3The shift on the fly system generates gear noises.
(The fuel economy is bad in the 2H mode.)
Function of circuitÐ
Fail conditionWhen the vehicle is run in the 2H mode, the shift on the fly system generates gear
noises or the front wheel gears are engaged to generate a shock.
D04R200021

4B2±113
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn on the starter switch.
Is any of the trouble codes 41 (P1741), 42 (P1773), 43 (P1743)
and 55 (P1755) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 2
2Is any of the trouble codes 13 (P1735), 14 (P1731), 15 (P1736),
16 (P1737), 24 (P1733), and 27 (P1738) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 3
3Is the trouble code 17 (P1774) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 4
41. Turn on the starter switch.
2. The car stops, engine speed is less than 1500 rpm, the AT
selector is N position, and select the TOD switch to the 4L
position.
Do the front lamp and rear lamp in the indicator blink?
Go to Step 5
Examine the
trouble based on
ªTrouble
Diagnosis
Depending on the
Status of TOD
Indicatorº.
51. Step on the brake pedal.
Is the transfer changed to the 4L mode?The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 6
6When the vehicle is moved forth and back, is the transfer changed
to the 4L mode?The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 7
7Does the continuity corresponding to the encoder position
between the terminals comply with the 4L position in the following
table (continuity)?Examine the
trouble based on
ªTrouble
diagnosis
Depending on
The Status of
TOD Indicatorº.
Go to Step 8
81. Step on the brake pedal.
Is the battery voltage observed between the terminal 37 and 47?
Go to Step 10Go to Step 9
91. Turn off the starter switch.
2. Disconnect the ECU connector (C±37) and the brake switch
connector (I±31).
Is there the continuity between the connector terminal (C±37) 15
and (I±31) 4?The brake switch
is abnormal.
Repair or replace
the brake switch.
Go to
Step 13
Repair the
harness.
Go to
Step 13
101. Select the AT selector to the N position.
Is the voltage between the terminals ranged within the following
table (voltage)?
Go to Step 12Go to Step 11
111. Turn off the starter switch.
2. Disconnect the ECU connector (C±37).
3. Disconnect the AT mode switch connector (E±41).
Is there the continuity between the following connector terminals?
(C±37)6 and (E±41)8 (C±37)19 and (E±41)7 (C±37)5 and
(E±41)6
Repair or replace
the AT mode
switch.
Go to
Step 13
Repair the circuit
which has no
continuity.
Go to
Step 13

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±116
StepActionYe sNo
11. Turn on the starter switch.
Is any of the trouble codes 41 (P1741), 42 (P1773), 43 (P1743)
and 55 (P1755) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 2
2Is any of the trouble codes 13 (P1735), 14 (P1731), 15 (P1736),
16 (P1737), 24 (P1733), and 27 (P1738) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 3
3Is the trouble code 17 (P1774) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 4
41. Turn on the starter switch.
2. The car stops, engine speed is less than 1500 rpm, the AT
selector is N position, and select the TOD switch to the TOD
position.
Do the front, rear, and AUTO lamps in the indicator blink?
Go to Step 5
Examine the
trouble based on
ªTrouble
Diagnosis
Depending on the
Status of TOD
Indicatorº.
51. Step on the brake pedal.
Is the transfer changed to the TOD mode?The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 6
6When the vehicle is moved forth and back, is the transfer changed
to the TOD mode?The phenomenon
is not
reproduced.
Refer to
ªTrouble
intermittently
observedº.
Go to Step 7
7Is the continuity corresponding to the encoder position between
the terminals ranged within the any case (case 1, 2 and 3) of TOD
position in the following table (continuity)?Examine the
trouble based on
ªTrouble
diagnosis
Depending on
The Status of
TOD Indicatorº.
Go to Step 8
81. Step on the brake pedal.
Is the battery voltage observed between the terminal 37 and 47?
Go to Step 10Go to Step 9
91. Turn off the starter switch.
2. Disconnect the ECU connector (C±37) and the brake switch
connector (I±31).
Is there the continuity between the connector terminal (C±37) 15
and (I±31) 4?The brake switch
is abnormal.
Repair or replace
the brake switch.
Go to
Step 13
Repair the
harness.
Go to
Step 13
101. Select the AT selector to the N position.
Is the voltage between the terminals ranged within the following
table (voltage)?
Go to Step 12Go to Step 11
111. Turn off the starter switch.
2. Disconnect the ECU connector (C±37) and brake switch
connector (I±31).
3. Disconnect the AT mode switch connector (E±41).
Is there the continuity between the following connector terminals?
(C±37)6 and (E±41)8 (C±37)19 and (E±41)7 (C±37)5 and
(E±41)6
Repair or replace
the AT mode
switch.
Go to
Step 13
Repair the circuit
which has no
continuity.
Go to
Step 13

5A±37
BRAKE CONTROL SYSTEM
Diagnostic Trouble Codes (DTCs)
When the warning light in the meter remains ON, the
EHCU stores the fault identification and disables the
ABS.
How to display and erase DTCs:
NOTE:

DTCs can be displayed also by TECH 2. Use
ªDiagnostic Trouble Codesº mode.1. How to start DTC display:

Confirm that the vehicle has come to a complete
stop (with the wheels standing still) and that the
brake pedal is not depressed. (Unless these two
condition are satisfied, DTC display cannot be
started.)

With IGN OFF, connect #12 terminal with #4
terminal or # 5 terminal (GND) . Then turn IGN ON.
The DLC is located behind the driver side kick panel
350R200001

Keep #12 terminal connected with #4 terminal or # 5
terminal (GND) during DTC display. (If #12 terminal
is separated from #4 terminal or # 5 terminal (GND)
during display, display will stop.)
2. DTC display:

DTC is displayed by blinking warning light.

Double-digit display.

First, normal DTC 12 is displayed three times and
then any other DTCs are displayed three times. (If
no other DTCs have been stored, the display of DTC
12 will be repeated.)3. How to erase code:

Conduct brake switch ON/OFF operation 6 or more
times within 3 seconds of self-diagnosis startup.

The code cannot be erased if more than 3 seconds
have passed since self-diagnosis startup, or if
self-diagnosis has started with brake switched on
(brake pedaled).
B05RW005

5C±3 POWER±ASSISTED BRAKE SYSTEM
The master cylinder contains two pistons that supply the
hydraulic pressure for a dual±circuit braking system. The
primary piston provides the fluid pressure to the front
brakes, while the secondary piston provides the fluid
pressure to the rear brakes. If the pressure is lost from
either system, the remaining system will function to stop
the vehicle.CAUTION:
1. The master cylinder is not repairable. If found
defective, it must be replaced as a complete
assembly.
2. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system. (Refer to
Bleeding Brake
Hydraulic System
in this section.)
3. The torque values specified are for dry,
unlubricated fasteners.
4. Perform service operations on a clean bench free
from all mineral oil materials.
Brake Booster
331RS001
This booster is a tandem vacuum unit with a diaphragm
effective diameter 205mm (8.072 in) + 230mm (9.056 in).
In normal operating mode, with the service brakes in the
released position, the tandem vacuum booster operates
with vacuum on both sides of its diaphragms. When the
brakes are applied, air at atmospheric pressure is
admitted to both sides of the diaphragm to provide the
power assist. When the service brake is released, the
atmospheric air is shut off from both sides of the
diaphram. The air is then drawn from the booster through
the vacuum check valve to the vacuum source.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system.
2. The torque values specified are for dry,
unlubricated fasteners.
3. The vacuum booster is not repairable and must be
replaced as complete assembly.

5C±5 POWER±ASSISTED BRAKE SYSTEM
Leading/Trailing Drum Brakes (4y2 Model)
A05RS003
This drum brake assembly is a leading/trailing shoe
design. Both brake shoes are held against the wheel
cylinder pistons by the upper return spring and to the fixed
anchor plate by the lower return spring. When the brakes
are applied, the wheel cylinder pistons expand pushing
both shoes out contact the drum.
With forward wheel rotation, the forward brake shoe will
wrap into the drum and becomes self-energized.
With reverse wheel rotation, the rear brake shoe is
self-energized. Force from the brake shoes is transferred
to the anchor plate through the braking plate to the axle
flange. Adjustment is automatic and occurs on any
service brake application. Also, with leading/trailing
brakes, it is normal for the front shoe to wear at a faster
rate than the rear shoe.

5C±63 POWER±ASSISTED BRAKE SYSTEM
The master cylinder contains two pistons that supply the
hydraulic pressure for a dual±circuit braking system. The
primary piston provides the fluid pressure to the front
brakes, while the secondary piston provides the fluid
pressure to the rear brakes. If the pressure is lost from
either system, the remaining system will function to stop
the vehicle.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system. (Refer to
Bleeding Brake
Hydraulic System
in this section.)
2. The torque values specified are for dry,
unlubricated fasteners.
3. Perform service operations on a clean bench free
from all mineral oil materials.
Brake Booster
331R200001
This booster is a tandem vacuum unit with a diaphragm
effective diameter 205mm + 230mm (8.07in + 9.06in). In
normal operating mode, with the service brakes in the
released position, the tandem vacuum booster operates
with vacuum on both sides of its diaphragms. When the
brakes are applied, air at atmospheric pressure is
admitted to both sides of the diaphragm to provide the
power assist. When the service brake is released, the
atmospheric air is shut off from both sides of the
diaphram. The air is then drawn from the booster through
the vacuum check valve to the vacuum source.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system.
2. The torque values specified are for dry,
unlubricated fasteners.
3. The vacuum booster is not repairable and must be
replaced as complete assembly.