2002 ISUZU AXIOM Service Repair Manual

INTELLIGENT SUSPENSION3F±5
Vertical G-Sensor
Front G-sensors installed inside front actuators and the
rear G-sensor installed on the rear left frame side detect
the vehicle vertical gravity and send a signal to the Control
Unit.
Lateral G-Sensor
The G-sensor installed inside the Control Unit detects the
vehicle turning speed and sends a signal to the Control
Unit.
Acronyms and Abbreviations
Several acronyms and abbreviations are commonly used
throughout this section:
BATT
Battery
DLC
Data Link Connector
DTC
Diagnostic Trouble Code
FL
Front Left
FR
Front Right
GND
Ground
HARN
Harness
IG
Ignition
PCM
Powertrain Control Module
RL
Rear Left
RR
Rear Right
SW
Switch
W/L
Warning Lamp
Vout
Voltage output
General Diagnosis
General Information
Intelligent Suspension Control troubles can be classified
into two types, those which can be detected by the
warning lamp and those which can be detected as a
vehicle abnormality by the driver.
In either case, locate the fault in accordance with
theªBASIC DIAGNOSTIC FLOWCHARTº and repair.
Please refer to
Section 3 for the diagnosis of mechanical
troubles such as abnormal noise, vehicle pulls, excessive
tire wear, wheel hop and shimmy, shake or vibration.
Service Precautions
Required Tools and Items:

Box Wrench

Special Tool
Some diagnosis procedures in this section require the
installation of a special tool.
J-39200 High Impedance Multimeter
When circuit measurements are requested, use a
circuit tester with high impedance.
Computer System Service Precautions
The Intelligent Suspension Control interfaces directly
with the Control Unit which is a control computer that is
similar in some regards to the Powertrain Control Module.
These modules are designed to withstand normal current
draws associated with vehicle operation. However care
must be taken to avoid overloading any of the Control Unit
circuits. In testing for opens or shorts, do not ground or
apply voltage to any of the circuits unless instructed to do
so by the appropriate diagnostic procedure. These
circuits should only be tested with a high impedance
multimeter (J-39200) or special tools as described in this
section. Power should never be removed or applied to
any control module with the ignition in the ªONº
position.Before removing or connecting battery cables,
fuses or connectors, always turn the ignition switch to
theªOFFº position.
General Service Precautions
The following are general precautions which should be
observed when servicing and diagnosing the Intelligent
Suspension Control and/or other vehicle systems. Failure
to observe these precautions may result in Intelligent
Suspension Control damage.

If welding work is to be performed on the vehicle using
an electric arc welder, the Control Unit connectors
should be disconnected before the welding operation
begins.

The Control Unit connectors should never be
connected or disconnected with the ignitionªONº.
Parts Handling
Be careful when handling the actuator, control unit, or
G-sensor. They should not be dropped or thrown,
because the semi-conductor G-sensor tip damage may
result.

3F±6INTELLIGENT SUSPENSION
FLASHING CODES
1. ON BOARD DIAGNOSIS (SELF-DIAGNOSIS)
1. The Control Unit conducts a self-test of most of the
wiring and components in the system each time the
key is turned ON. If a fault is detected the Control
Unit will store a Diagnostic Trouble Code (DTC) in
memory. It's a number that corresponds to a
specific problem.
2. When the problem detected is important: the
warning lamp turns on until the fault is repaired and
the Control Unit memory is cleared.
2. DIAGNOSTIC TROUBLE CODES (DTC)
1. DTC can be expressed by flashing times of warning
lamp by shorting together terminals 3 and 4 or 5 of
the Diagnosis Connector (C-39) located left side of
instrument panel.
350R200002
Normal
F03RY00001
Abnormal
F03R200001
Legend
(1) Diagnostic Trouble Code 2
(2) Diagnostic Trouble Code 3

INTELLIGENT SUSPENSION3F±7
It depends below in the case that the code that also,
shows a malfunction place is added.
F03R200002
Legend
(1) Diagnostic Trouble Code 2
(2) Diagnostic Trouble Code 3 + Position Code 2
Position Code
1: Actuator Front RH, G-sensor Front RH
2: Actuator Front LH, G-sensor Front LH
3: Actuator Rear RH, G-sensor Rear
4: Actuator Rear LH, Lateral G-sensor
2. After this, the warning lamp will be OFF for 3.5
seconds and then will flash each DTC.
a. When there are more than 9 flashes this means
that the indicator is constantly flashing, OFF for
4 seconds ON for 0.5 seconds. In this case there
is no DTC stored in memory.
b. When there are less than 9 flashes you will see
DTC codes in ascending order.
CLEAR DTC
Remark: If you clear the DTC (Diagnosis Trouble Codes)
you will not be able to read any codes recorded during the
last Trouble.
Remark: To be able to use the DTC again to identify a
problem you will need to reproduce the fault or the
problem. This may require a new test drive or just turning
the ignition on (this depends on the nature of the fault).
1. Short the Diagnosis Connector C-39 terminal 3 to
terminal 4 or 5 (ground).

IF it is flashing and the flash is 0.5 seconds ON and 4
seconds OFF without interruption, this means that
there is no DTC. The DTCs are already cleared.
350R200002
2. IF a code is flashed, wait until the lamp is flashing.
3. Conduct brake switch ON/OFF 6 or more times on
condition that one operation is within 2 seconds.

3F±8INTELLIGENT SUSPENSION
INTERMITTENT CONDITIONS
If the Warning Lamp flashes a diagnostic trouble code as
intermittent, or if after a test drive a DTC does not
reappear though the detection conditions for this DTC are
present: the problem is most likely a faulty electrical
connection or loose wiring. Terminals and grounds should
always be the prime suspect. Intermittents rarely occur
inside sophisticated electronic components such as the
Control Unit.
Use the DTC information to understand which wires and
sensors are involved.
When an intermittent problem is encountered, check
suspect circuits for:
1. Poor terminal to wire connection.
2. Terminals not fully seated in the connector body
(backed out).
3. Improperly formed or damaged terminals.
4. Loose, dirty, or corroded ground connections:
HINT: Any time you have an intermittent in more than
one circuit, check whether the circuits share a
common ground connection.
5. Pinched or damaged wires.
6. Electro-Magnetic Interference (EMI):
HINT: Check that all wires are properly routed away
from spark plug wires, distributor wires, coil, and
generator. Also check for improperly installed
electrical options, such as lights, 2-way radios, etc.
BULB CHECK
When the starter switch is turned on in the normal state,
the Control Unit turns on the Warning Lamp to check the
bulb. After the engine starts, the Warning Lamp turns off.
F03RY00003
DTC CHECK
1. Diagnosis Trouble Codes (DTC) have been identified
by FLASHING CODES.
2. You have written the list of the DTC. The order of the
malfunctions has no meanings for this Control Unit.
Usually only one or two malfunctions should be set for
a given problem.
3. Check directly the DTCs you identified. The DTC are
sorted by number:
DIAGNOSTIC TROUBLE CODES.

INTELLIGENT SUSPENSION3F±9
Basic Diagnosis Flow
C07RY00022

3F±10INTELLIGENT SUSPENSION
Circuit Diagram
826R200008

INTELLIGENT SUSPENSION3F±11
826R200009

3F±12INTELLIGENT SUSPENSION
826R200010