2002 ISUZU AXIOM suspension

INTELLIGENT SUSPENSION3F±19
DTC3 Actuator Coil/Position Sensor Open Circuit or Short
Circuit Description
The A, B, C, and D are the actuator motor coil terminals.
DC 12V driving voltage is applied between terminals A
and C and terminals B and D so that the shock absorber
oil valves are rotated at every 7.5
step feed.
The PSW is actuator position signal and detects relative
angles between the piston±rod and the control-rod. The
actuator outputs the PSW to the control unit.
Diagnostic Aids

Inspect the wiring for poor electrical connections
between the control unit 16 way connector and the
actuator connectors. Look for possible bent, backed
out, deformed, or damaged terminals. Check for
weak terminal tension as well.
Also check for a chafed wire that could short to bare
metal or other wiring. Inspect for a broken wire inside
the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
DTC3 Actuator Coil/Position Sensor Open Circuit or Short
StepActionValue(s)Ye sNo
11. Turn off the starter switch.
2. Disconnect the actuator connectors C±46, C±31,
C±9, F±8, and F±7.
Is there continuity between the connector C±9
terminals 1 and 2?
ÐGo to Step 2Go to Step 3
2Is there continuity between the connector C±9
terminals 3 and 4?
ÐGo to Step 4Go to Step 3
3Replace the actuator FR.
ÐGo to Step 4Ð
4Is there continuity between the connector C±31
terminals 1 and 2?
ÐGo to Step 5Go to Step 6
5Is there continuity between the connector C±31
terminals 3 and 4?
ÐGo to Step 7Go to Step 6
6Replace the actuator FL.
ÐGo to Step 7Ð
7Is there continuity between the connector F±7
terminals 3 and 4?
ÐGo to Step 8Go to Step 9
8Is there continuity between the connector F±7
terminals 7 and 8?
ÐGo to Step 10Go to Step 9
9Replace the rear shock absorber RR.
ÐGo to Step 10Ð
10Is there continuity between the connector F±8
terminals 3 and 4?
ÐGo to Step 11Go to Step 12
11Is there continuity between the connector F±8
terminals 7 and 8?
ÐGo to Step 13Ð
12Replace the rear shock absorber RL.
ÐGo to Step 13Ð
13Is there continuity between the connector C±9 terminal
1 and connector C±46 terminal 4?
ÐGo to Step 14Go to Step 15
14Is there continuity between the connector C±9 terminal
3 and connector C±46 terminal 17?
ÐGo to Step 16Go to Step 15
15Repair the circuit.
ÐGo to Step 16Ð

3F±20INTELLIGENT SUSPENSION
DTC3 Actuator Coil/Position Sensor Open Circuit or Short (Cont'd)
StepNo Ye s Value(s) Action
16Is there continuity between the connector C±9 terminal
2 and connector C±46 terminal 5?
ÐGo to Step 17Go to Step 18
17Is there continuity between the connector C±9
terminals 4 and connector C±46 terminal 18?
ÐGo to Step 19Go to Step 18
18Repair the circuit.
ÐGo to Step 19Ð
19Is there continuity between the connector C±31
terminal 1 and connector C±46 terminal 6?
ÐGo to Step 20Go to Step 21
20Is there continuity between the connector C±31
terminal 3 and connector C±46 terminal 19?
ÐGo to Step 22Go to Step 21
21Repair the circuit.
ÐGo to Step 22Ð
22Is there continuity between the connector C±31
terminal 2 and connector C±46 terminal 7?
ÐGo to Step 23Go to Step 24
23Is there continuity between the connector C±31
terminal 4 and connector C±46 terminal 20?
ÐGo to Step 25Go to Step 24
24Repair the circuit.
ÐGo to Step 25Ð
25Is there continuity between the connector F±7 terminal
4 and connector C±46 terminal 8?
ÐGo to Step 26Go to Step 27
26Is there continuity between the connector F±7 terminal
8 and connector C±46 terminal 21?
ÐGo to Step 28Go to Step 27
27Repair the circuit.
ÐGo to Step 28Ð
28Is there continuity between the connector F±7 terminal
3 and connector C±46 terminal 9?
ÐGo to Step 29Go to Step 30
29Is there continuity between the connector F±7 terminal
7 and connector C±46 terminal 22?
ÐGo to Step 31Go to Step 30
30Repair the circuit.
ÐGo to Step 31Ð
31Is there continuity between the connector F±8 terminal
4 and connector C±46 terminal 10?
ÐGo to Step 32Go to Step 33
32Is there continuity between the connector F±8 terminal
8 and connector C±46 terminal 23?
ÐGo to Step 34Go to Step 33
33Repair the circuit.
ÐGo to Step 34Ð
34Is there continuity between the connector F±8 terminal
3 and connector C±46 terminal 11?
ÐGo to Step 35Go to Step 36
35Is there continuity between the connector F±8 terminal
7 and connector C±46 terminal 24?
ÐGo to Step 37Go to Step 36
36Repair the circuit.
ÐGo to Step 37Ð
371. Disconnect the terminals C±45, C±8, C±30, F±7,
and F±8.
Is there continuity between the connector±terminal
C45±29 and C8±6, C45±37 and C30±6, C45±33 and
F7±2, C45±41 and F8±2?
ÐGo to Step 38Go to Step 41

INTELLIGENT SUSPENSION3F±21
DTC3 Actuator Coil/Position Sensor Open Circuit or Short (Cont'd)
StepNo Ye s Value(s) Action
38Is there continuity between the connector C±46
terminal 1 (GND) and the connector C±45 terminals 29,
33, 37, and 41?
ÐGo to Step 41Go to Step 39
39Is there the continuity between connector-terminal
C45±27 and C45±35, C45±31 and C45±39, C45±32
and C45±40, and C45±34 and C45±42?
ÐGo to Step 41Go to Step 40
40Is there the continuity between connector C±46
terminal 1 and connector C±45 terminals 27, 31, 32,
and 34?
ÐGo to Step 41Go to Step 42
41Repair the circuit.
ÐGo to Step 44Ð
421. If all steps are correct, replace following units one by
one in the following order. Give a test drive and if
normal, reinstall it.
1) actuator FR, 2) actuator FL, rear shock
absorber, 3) RR and 4) RL.
Does the DTC3 remain?
ÐGo to Step 43Go to Step 44
43Replace the control unit.
ÐGo to Step 44Ð
441. Reconnect all components, ensure all components
are properly mounted.
2. Clear the DTC.
Was this step finished?
Ð
Go to ªBasic
Diagnosis
Flowº.
Go to Step 44

3F±22INTELLIGENT SUSPENSION
DTC4 G-Sensor Open Circuit or Short
Circuit Description
The G-sensor sends the voltage (Vout) corresponding to
the vehicle vertical gravity to the control unit.
The control unit supplies DC 5V power (Vcc) to each
G-sensor.
The control unit watches the G-sensor operation through
Vcc signal.
Diagnostic Aids

Inspect the wiring for poor electrical connections
between the control unit connectors and the actuator
connectors. Look for possible bent, backed out,
deformed, or damaged terminals. Check for weak
terminal tension as well.
Also check for a chafed wire that could short to bare
metal or other wiring. Inspect for a broken wire inside
the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
DTC4 G-Sensor Open Circuit or Short
StepActionValue(s)Ye sNo
11. Turn off the starter switch.
2. Disconnect the connectors C±45, C±44, C±8,
C±30, and F±6.
Is there the continuity between the connector-terminal
C45±28 and C8±5, C45±30 and C30±5, and C44±45
and F6±1?
ÐGo to Step 2Go to Step 5
2Is there continuity between the connector-terminal
C45±27 and C8±3, C45±31 and C30±3, and C44±44
and F6±2?
ÐGo to Step 3Go to Step 5
3Is there the continuity between the connector-terminal
C45±36 and C8±2, C45±38 and C30±2, and C44±56
and F6±3?
ÐGo to Step 4Go to Step 5
41. Disconnect the connectors C±46, C±45, and C±44.
Is there the continuity between the connector-terminal
C45±28 and C45±35, C45±30 and C45±39, C44±45
and C44±55, C45±27 and C45±35, C45±31 and
C45±39, C44±44 and C44±55, C45±36 and C45±35,
C45±38 and C45±39, and C44±56 and C44±55?
ÐGo to Step 5Go to Step 7
5Repair the circuit.
ÐGo to Step 6Ð
6Replace following units one by one in the following
order. Give a test drive and if normal, reinstall it.
1) G3-sensor 2) Actuator FL 3) Actuator FR 4)
Control Unit
ÐGo to Step 7Ð
71. Reconnect all components, ensure all components
are properly mounted.
2. Clear the DTC.
Was this step finished?
Ð
Go to ªBasic
Diagnosis
Flow.º
Go to Step 7

INTELLIGENT SUSPENSION3F±23
DTC5 Vehicle Speed Sensor Open Circuit or Short
Circuit Description
Output speed information is provided to the control unit by
the vehicle speed sensor. The vehicle speed sensor
produces a pulsing AC voltage. The AC voltage level and
number of pulses increases as the speed of the vehicle
increases. The control unit then converts the pulsing
voltage to vehicle speed.
Diagnostic Aids

Inspect the wiring for poor electrical connections
between the control unit 48 way connector and the
speed sensor connectors. Look for possible bent,
backed out, deformed, or damaged terminals. Check
for weak terminal tension as well.
Also check for a chafed wire that could short to bare
metal or other wiring. Inspect for a broken wire inside
the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
DTC5 Vehicle Speed Sensor Open Circuit or Short
StepActionValue(s)Ye sNo
11. Jack up and support the rear axle on the stand.
2. Change the transfer mode to 2WD, using TOD
switch on instrument panel.
3. Shift the transmission lever in a forward position
and rotate the rear wheels.
Does the speedo-meter operate?
ÐGo to Step 2Go to Step 3
21. Open the throttle and rev up engine speed.
2. Using a volt meter, measure the voltage between
the meter B connector I±23 terminals 7 and 16
(GND).
Does the voltage change alternately at the specified
values?
0V and 12VGo to Step 7Go to Step 5
31. Turn off the starter switch and disconnect the
control connectors C±46 and C±44.
2. Check the continuity between the vehicle speed
sensor connector terminal 3 and meter B connector
I±23 terminal 7.
Is there continuity?
ÐGo to Step 4Go to Step 6
41. Check the continuity between the control unit
connector C±46 terminal 1 and control unit
connector C±44 terminal 48.
Is there continuity?
ÐGo to Step 5Go to Step 6
5Repair or replace the vehicle speed sensor.
ÐGo to Step 8Ð
6Repair the circuit between the vehicle speed sensor
connector terminal 3 and the meter B connector I±23
terminal 7 or the circuit between the control unit
connector C±44 terminal 48 and the speed sensor
connector terminal 3.
ÐGo to Step 8Ð

3F±24INTELLIGENT SUSPENSION
DTC5 Vehicle Speed Sensor Open Circuit or Short (Cont'd)
StepNo Ye s Value(s) Action
7Repair the circuit between the connector H±6 terminal
16 and the control unit connector C±44 terminal 48 or
replace the control unit.
ÐGo to Step 8Ð
81. Reconnect all components, ensure all components
are properly mounted.
2. Clear the DTC.
Was this step finished?
Ð
Go to ªBasic
Diagnosis
Flow.º
Go to Step 8
About the vehicle speed sensor connector termainal 3,
Refer to section
Wiring System in Body and Accessories.

INTELLIGENT SUSPENSION3F±25
DTC6 Stop Lamp Switch Open Circuit or Short
Circuit Description
The brake switch is used to indicate brake pedal status.
The normally opened brake switch signal voltage circuit is
opened.
Brake switch supplies a B+ signal on circuit RED to the
control unit when the brakes are applied. The control unit
uses this signal to work dive control when the brakes are
applied.
Diagnostic Aids

Inspect the wiring for poor electrical connections at
the control unit and brake switch. Look for possible
bent, backed out, deformed or damaged terminals.
Check for weak terminal tension as well. Also check
for a chafed wire that could short to bare metal or
other wiring. Inspect for a broken wire inside the
insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

Check customer driving habits and/or unusual driving
conditions (i.e. stop and go, highway).

Check brake switch for proper mounting and
adjustment.
DTC6 Stop Lamp Switch Open Circuit or Short
StepActionValue(s)Ye sNo
11. With the engine ªoffº, turn the ignition switch ªonº. If
ABS code is set, check applicable fuse.
2. Apply then release the brake pedal.
Does the brake lamp come on when the brake pedal is
applied and does it come off when the brake pedal is
released?
Ð
Go to
Diagnostic
Aids
Go to Step 2
21. Connect the test light to ground.
2. Back probe ignition feed circuit terminal I±31
terminal 1 at the brake switch.
Is the test light ªonº?
ÐGo to Step 3Go to Step 4
31. Connect the test light to ground.
2. Back probe circuit terminal I±31 terminal 4 at the
brake switch.
Is the test light ªoffº?
ÐGo to Step 7Go to Step 5
4Repair the open in battery feed circuit terminal I±31
terminal 1 to the brake switch.
If fuse is open, check circuit terminal I±31 terminal 4 for
a short to ground.
Is the replacement complete?
ÐGo to Step 13Ð
5Disconnect brake switch connector I±31 and ignition
switch ªonº.
Is the test light ªonº?
ÐGo to Step 8Go to Step 6
6Check the brake switch short (I±31 terminal 1 and I±31
terminal 4).
Was a problem found?
ÐGo to Step 9Go to Step 10
7Check circuit terminal I±31 terminal 4 for a short to
voltage.
Ignition switch ªonº.
Is the test light ªonº?
ÐGo to Step 8Go to Step 10
81. Disconnect the control unit connector C±44.
2. Check circuit terminal I±31 terminal 4 for a short to
voltage.
Was a problem found?
ÐGo to Step 13Go to Step 10

3F±26INTELLIGENT SUSPENSION
DTC6 Stop Lamp Switch Open Circuit or Short (Cont'd)
StepNo Ye s Value(s) Action
9Replace the brake switch.
Is the replacement complete?
ÐGo to Step 13Ð
101. Turn the ignition ªoffº.
2. Reconnect the control unit connector C±44
Turn the ignition ªonº.
Does the brake lamp come on when the brake pedal is
applied and does it come off when the brake pedal is
released?
Ð
Go to
Diagnostic
Aids
Go to Step 11
11Check the control unit for faulty or intermittent
connections.
Was a problem found and corrected?
ÐGo to Step 13Go to Step 12
12Replace the control unit.
Is the replacement complete?
ÐGo to Step 13Ð
131. After the repair is complete, clear the DTC.
2. Conduct a test drive.
3. Review the DTC.
Has the last test failed or is the current DTC displayed?
Ð
Begin diagnosis
again
Go to
Step 1
Go to Repair
verified