2002 ISUZU AXIOM check engine light

5C±66
POWER±ASSISTED BRAKE SYSTEM
Diagnosis
Road Testing The Brakes
Brake Test
Brakes should be tested on a dry, clean, reasonably
smooth and level roadway. A true test of brake
performance cannot be made if the roadway is wet,
greasy or covered with loose dirt where all tires do not grip
the road equally. Testing will also be adversely affected if
the roadway is crowned so as to throw the weight of the
vehicle toward wheels on one side or if the roadway is so
rough that wheels tend to bounce. Test the brakes at
different vehicle speeds with both light and heavy pedal
pressure; however, avoid locking the wheels and sliding
the tires. Braking without locking the tires will stop the
vehicle in less distance than braking to a skid (which has
no brake efficiency). More tire to road friction is present
while braking without locking the tires than braking to a
skid.
The standard brake system is designed and balanced to
avoid locking the wheels except at very high deceleration
levels.
It is designed this way because the shortest stopping
distance and best control is achieved without brake
lock±up.
Because of high deceleration capability, a firmer pedal
may be felt at higher deceleration levels.
External Conditions That Affect Brake Performance
1. Tires: Tires having unequal contact and grip on the
road will cause unequal braking. Tires must be
equally inflated, identical in size, and the thread
pattern of right and left tires must be approximately
equal.
2. Vehicle Loading: A heavily loaded vehicle requires
more braking effort.
3. Wheel Alignment: Misalignment of the wheels,
particularly in regard to excessive camber and caster,
will cause the brakes to pull to one side.
Brake Fluid Leaks
With engine running at idle and the transmission in
ªNeutralº, depress the brake pedal and hold a constant
foot pressure on the pedal. If pedal gradually falls away
with the constant pressure, the hydraulic system may be
leaking.
Check the master cylinder fluid level. While a slight drop in
the reservoir level will result from normal lining wear, an
abnormally low level in reservoir indicates a leak in the
system. The hydraulic system may be leaking internally
as well as externally. Refer to
Master Cylinder Inspection.
Also, the system may appear to pass this test but still
have slight leakage. If fluid level is normal, check the
vacuum booster push rod length. If an incorrect length
push rod is found, adjust or replace the push rod. Check
the brake pedal travel and the parking brake adjustment.
When checking the fluid level, the master cylinder fluid
level may be lower than the ªMAXº mark if the front and
rear linings are worn. This is normal.
Warning Light Operation
When the ignition switch is in the START position, the
ªBRAKEº warning light should turn on and go off when the
ignition switch returns to the ON position.
The following conditions will activate the ªBRAKEº light:
1. Parking brake applied. The light should be on
whenever the parking brake is applied and the ignition
switch is on.
2. Low fluid level. A low fluid level in the master cylinder
will turn the ªBRAKEº light on.
3. During engine cranking the ªBRAKEº light should
remain on. This notifies the driver that the warning
circuit is operating properly.

5C±71 POWER±ASSISTED BRAKE SYSTEM
NOTE: Do not allow the fluid level in the reservoir to go
below the half±way mark.
12. Reconnect the brake pipe (1) to the master cylinder
and tighten the pipe.
13. Depress the brake pedal slowly once and hold it
depressed.
14. Loosen the rear wheel brake pipe (1) at the master
cylinder.
15. Retighten the brake pipe, then release the brake
pedal slowly.
16. Repeat steps 13 through 15 until no air comes out of
the port when the brake pipe is loosened
NOTE: Be very careful not to allow the brake fluid to come
in contact with painted surfaces.
330R200004
17. Bleed the air from the front wheel brake pipe
connection (2) by repeating steps 7 through 16.
Bleeding the Caliper
18. Bleed the air from each wheel in the order listed
below:

Right rear caliper or wheel cylinder

Left rear caliper or wheel cylinder

Right front caliper

Left front caliper
Conduct air bleeding from the wheels in the above
order. If no brake fluid comes out, it suggests that air
is mixed in the master cylinder. In this case, bleed air
from the master cylinder in accordance with steps 7
through 17, and then bleed air from the caliper or
wheel cylinder.
19. Place the proper size box end wrench over the
bleeder screw.
20. Cover the bleeder screw with a transparent tube, and
submerge the free end of the transparent tube in a
transparent container containing brake fluid.
21. Pump the brake pedal slowly three (3) times
(once/sec), then hold it depressed.
22. Loosen the bleeder screw until fluid flows through the
tube.
23. Retighten the bleeder screw.24. Release the brake pedal slowly.
25. Repeat steps 21 through 24 until the air is completely
removed.
It may be necessary to repeat the bleeding procedure
10 or more times for front wheels and 15 or more
times for rear wheels.
26. Go to the next wheel in the sequence after each wheel
is bled.
Be sure to monitor reservoir fluid level.
27. Depress the brake pedal to check if you feel
ªsponginessº after the air has been removed from all
wheel cylinders and calipers.
If the pedal feels ªspongyº, the entire bleeding
procedure must be repeated.
28. After the bleeding operation is completed on the each
individual wheel, check the level of the brake fluid in
the reservoir and replenish up to the ªMAXº level as
necessary.
29. Attach the reservoir cap.
If the diaphragm inside the cap is deformed, reform
it and install.
30. Stop the engine.
Flushing Brake Hydraulic System
It is recommended that the entire hydraulic system be
thoroughly flushed with clean brake fluid whenever new
parts are installed in the hydraulic system. Approximately
one quart of fluid is required to flush the hydraulic system.
The system must be flushed if there is any doubt as to the
grade of fluid in the system or if fluid has been used which
contains the slightest trace of mineral oil. All rubber parts
that have been subjected to a contaminated fluid must be
replaced.
Brake Pipes and Hoses
The hydraulic brake system components are
interconnected by special steel piping and flexible hoses.
Flexible hoses are used between the frame and the front
calipers, the frame and rear axle case and the rear axle
and the rear calipers.
When the hydraulic pipes have been disconnected for
any reason, the brake system must be bled after
reconnecting the pipe. Refer to
Bleeding the Brake
Hydraulic System
in this section.
Brake Hose Inspection
The brake hose should be inspected at least twice a year.
The brake hose assembly should be checked for road
hazard, cracks and chafing of the outer cover, and for
leaks and blisters. Inspect for proper routing and
mounting of the hose. A brake hose that rubs on
suspension components will wear and eventually fail. A
light and mirror may be needed for an adequate
inspection. If any of the above conditions are observed on
the brake hose, adjust or replace the hose as necessary.
CAUTION: Never allow brake components such as
calipers to hang from the brake hoses, as damage to
the hoses may occur.

5C±77 POWER±ASSISTED BRAKE SYSTEM
Brake Pedal
Checking Pedal Height
The push rod serves as the brake pedal stopper when the
pedal is fully released. Brake pedal height adjustment
should be performed as follows:
Adjust Brake Pedal
310R200002
1. Measure the brake pedal height after making sure the
pedal is fully returned by the pedal return spring.
Pedal height must be measured after starting the
engine and stepping on it several times.
Pedal Free Play: 6-10 mm (0.23-0.39 in)
Pedal Height: 173-185 mm (6.81-7.28 in)
NOTE: Pedal free play must be measured after turning
off the engine and stepping on the brake pedal firmly five
times or more.
2. If the measured value is not within the above range,
adjust the brake pedal as follows:
a. Disconnect the stoplight switch connector.
b. Loosen the stoplight switch lock nut.
c. Rotate the stoplight switch so that it moves away
from the brake pedal.
d. Loosen the lock nut (1) on the push rod.
e. Adjust the brake pedal to the specified height by
rotating the push rod in the appropriate direction.
f. Tighten the lock nut to the specified torque.
Torque: 20 N´m (15 lb ft)
g. Adjust the stoplight switch (2) to the specified
clearance (between the switch housing and the
brake pedal) by rotating the switch housing.
Clearance: 0.5±1.0 mm (0.02±0.04 in)
310RY00005
NOTE: While adjusting the stoplight switch, make sure
that the threaded part of the stoplight switch does not
push the brake pedal.
h. Tighten the stoplight switch lock nut.
i. Connect the stoplight switch connector.
Checking Pedal Travel
310R200002
1. Pedal height must be measured after starting the
engine and revving it several times to apply vacuum
to the vacuum booster fully.
NOTE: Pedal height must be 95 mm (3.7 in) or more
when about 50 kg (110.25 lb) of stepping force is applied.
2. If the measured value is lower than the above range,
air may still be present in the hydraulic system
Perform the bleeding procedure.

6A±4
ENGINE MECHANICAL (6VE1 3.5L)
Engine Diagnosis
First of all the engine diagnose to check the fuel quantity,
the engine level and the engine coolant level.
Hard Starting
1. Starting Motor Does Not Turn Over
Troubleshooting Procedure
Turn on headlights and starter switch.
Condition
Possible causeCorrection
Headlights go out or dim
considerably
Battery run down or under chargedRecharge or replace battery
considerablyTerminals poorly connectedClean battery posts and terminals
and connect properly
Starting motor coil circuit shortedOverhaul or replace
Starting motor defectiveOverhaul or replace
2. Ignition Trouble Ð Starting Motor Turns Over But Engine Does Not Start
Spark Test
Disconnect an ignition coil from any spark plug. Connect
the spark plug tester (For example J±26792), start the
engine, and check if a spark is generated in the spark plugtester. Before starting the engine, make sure that the
spark plug tester is properly grounded. To avoid electrical
shock, do not touch the part where insulation of the
ignition coil is broken while the engine is running.
Condition
Possible causeCorrection
Spark jumps across gapSpark plug defectiveClean, adjust spark gap or replace
Ignition timing incorrectRefer to Ignition System
Fuel not reaching fuel injector(s) or
engineRefer to item 3 (Trouble in fuel
system)
Valve timing incorrectAdjust
Engine lacks compressionRefer to item 4 (Engine lacks
compression)
No sparking takes placeIgnition coil disconnected or brokenConnect properly or replace
Electronic Ignition System with
moduleReplace
Poor connections in engine harnessCorrect
Powertrain Control Module cable
disconnected or defectiveCorrect or replace
3. Trouble In Fuel System
Condition
Possible causeCorrection
Starting motor turns over and spark
occurs but engine does not start
Fuel tank emptyFill
occurs but engine does not start.Water in fuel systemClean
Fuel filter cloggedReplace filter
Fuel pipe cloggedClean or replace
Fuel pump defectiveReplace
Fuel pump circuit openCorrect or replace
Evaporative Emission Control
System circuit cloggedCorrect or replace
Multiport Fuel Injection System faultyRefer to ªElectronic Fuel Injectionº
section

6D1±2
ENGINE ELECTRICAL (6VE1 3.5L)
Battery
General Description
The battery is completely sealed except for the two small
vent holes (2) on the side. These vent holes (2) permit the
escape of small amounts of gas generated by the battery.
This type of battery has the following advantages over
conventional batteries:
1. There is no need to add water during the entire
service life of the battery.
2. The battery is much less vulnerable to self discharge
than a conventional type battery.
Diagnosis
1. Visual Inspection
Inspect the battery for obvious physical damage, such as
a cracked or broken case, which would permit electrolyte
loss.
Replace the battery if obvious physical damage is
discovered during inspection.
Check for any other physical damage and correct it as
necessary.
2. Hydrometer Check
There is a built±in hydrometer (Charge test indicator(1))
at the top of the battery. It is designed to be used during
diagnostic procedures.
Before trying to read the hydrometer, carefully clean the
upper battery surface.
If your work area is poorly lit, additional light may be
necessary to read the hydrometer.
a. BLUE RING OR DOT VISIBLE(4) ± Go to Step 3.
b. BLUE RING OR DOT NOT VISIBLE(3) ± Replace
the battery.
061R200001
3. Voltage Check
1. Put voltmeter test leads to battery terminals.
a. VOLTAGE IS 12.4V OR ABOVE ± Go to Step 4
Load Test.
b. VOLTAGE IS UNDER 12.4V ± Go to procedure (2)
below.
2. Determine fast charge amperage from specification.
(See Main Data and Specifications in this section).
Fast charge battery for 30 minutes at amperage rate
no higher than specified value.
Take voltage and amperage readings after charge.
a. VOLTAGE IS ABOVE 16V AT BELOW 1/3 OF
AMPERAGE RATE ± Replace battery.
b. VOLTAGE IS ABOVE 16V AT ABOVE 1/3 OF
AMPERAGE RATE ± Drop charging voltage to 15V
and charge for 10 ± 15 hours. Then go to Step 4
Load Test.
c. VOLTAGE IS BETWEEN 12V AND 16V ±
Continue charging at the same rate for an
additional 3±1/2 hours. Then go to Step 4 Load
Test.
d. VOLTAGE BELOW 12V ± Replace the Battery.
4. Load Test
1. Connect a voltmeter and a battery load tester across
the battery terminals.
2. Apply 300 ampere load for 15 seconds to remove
surface charge from the battery. Remove load.
3. Wait 15 seconds to let battery recover. Then apply
specified load from specifications (See Main Data
and Specifications in this section).
Read voltage after 15 seconds, then remove load.
a. VOLTAGE DOES NOT DROP BELOW THE
MINIMUM LISTED IN THE TABLE ± The battery is
good and should be returned to service.
b. VOLTAGE IS LESS THAN MINIMUM LISTED ±
Replace the battery.
ESTIMATED TEMPERATURE
MINIMUM
VOLTAGE

F
CV
70219.6
60169.5
50109.4
4049.3
30±19.1
20±78.9
10±128.7
0±188.5
The battery temperature must be estimated by feel
and by the temperature the battery has been
exposed to for the preceding few hours.

6D3±17
STARTING AND CHARGING SYSTEM (6VE1 3.5L)
Charging System
General Description
The IC integral regulator charging system and its main
components are connected as shown in illustration.
The regulator is a solid state type and it is mounted along
with the brush holder assembly inside the generator
installed on the rear end cover.
The generator does not require particular maintenance
such as voltage adjustment.The rectifier connected to the stator coil has diodes to
transform AC voltage into DC voltage.
This DC voltage is connected to the output terminal of
generator.
F06RX002
General On±Vehicle Inspection
A basic wiring diagram is shown in the illustration. When
operating normally, the indicator bulb will come on when
the switch is turned on, and will then go out when the
engine starts. If the indicator operates abnormally, or if an
undercharged or overcharged battery condition occurs,
the following procedure may be used to diagnose the
charging system. Remember that an undercharged
battery is often caused by accessories being left on
overnight, or by a defective switch which allows a bulb,
such as a trunk or glove box light, to stay on.
Observe the following procedure:
1. Visually check belt and wiring.
2. Go to step 5. for vehicles without charge indicator
light.
3. Switch on, engine stopped, light should be on. If not,
detach harness at generator, ground ªLº terminal
lead.a. Lamp lights, replace or repair generator.
b. Lamp dose not light, locate open circuit between
grounding lead and ignition switch. Bulb may be
open.
4. Switch on, engine running at moderate speed. Light
should be off. If not, detach wiring harness at
generator.
a. If light goes off, replace or repair generator.
b. If light stays on, check for grounded ªLº terminal
wire in harness.
5. Battery undercharged or overcharged.
a. Detach wiring harness connector from generator.
b. With switch on, engine not running connect
voltmeter from ground to ªLº terminal in wiring
harness, and to ªIGº terminal. If used. Wiring
harness may connect to either ªLº or ªIGº or both.
c. Zero reading indicates open circuit between
terminal and battery. Connect as required.

6E±28
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Engine Component Locator Table
Number
NameLocation
1Linear Exhaust Gas Recirculation (EGR) ValveRear right side of the engine
2Throttle Position (TP) SensorOn the throttle body
3Intake Air Temperature (IAT) SensorOn the intake air duct near the throttle body
4Check Engine (MIL) LightOn the instrument panel beneath the
tachometer
5Positive Crankcase Ventilation (PCV) ValveOn the left of the cylinder head cover
6Air CleanerLeft front of the engine bay
7Mass Air Flow (MAF) SensorAttached to the air filter box
8Fuel RailOn the Common Chamber
9Fuel Pressure RegulatorRear side of the engine
10ION Sensing moduleBolted to the top of the Common Chamber
11Common ChamberTop of the engine
12EVAP Duty Solenoid ValveBolted to the front of the coolant pipe
13Fuse/Relay BoxAlong the inside of the right fender
14Manifold Absolute Pressure (MAP) SensorBolted to the top of the Common Chamber
15Throttle BodyBetween the intake air duct and the Common
Chamber
16Engine Coolant Temperature SensorOn the coolant crossover pipe at the front of
the engine, near the throttle body
17Power Train Control Module (PCM)Along the inside of the left fender

6E±33
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnosis
Strategy-Based Diagnostics
Strategy-Based Diagnostics
The strategy-based diagnostic is a uniform approach to
repair all Electrical/Electronic (E/E) systems. The
diagnostic flow can always be used to resolve an E/E
system problem and is a starting point when repairs are
necessary. The following steps will instruct the technician
how to proceed with a diagnosis:
1. Verify the customer complaint.

To verify the customer complaint, the technician
should know the normal operation of the system.
2. Perform preliminary checks.

Conduct a thorough visual inspection.

Review the service history.

Detect unusual sounds or odors.

Gather diagnostic trouble code information to
achieve an effective repair.
3. Check bulletins and other service information.

This includes videos, newsletters, etc.
4. Refer to service information (manual) system
check(s).

ªSystem checksº contain information on a system
that may not be supported by one or more DTCs.
System checks verify proper operation of the
system. This will lead the technician in an
organized approach to diagnostics.
5. Refer to service diagnostics.
DTC Stored
Follow the designated DTC chart exactly to make an
effective repair.
No DTC
Select the symptom from the symptom tables. Follow the
diagnostic paths or suggestions to complete the repair.
You may refer to the applicable component/system check
in the system checks.
No Matching Symptom
1. Analyze the complaint.
2. Develop a plan for diagnostics.
3. Utilize the wiring diagrams and the theory of
operation.
Combine technician knowledge with efficient use of the
available service information.
Intermittents
Conditions that are not always present are called
intermittents. To resolve intermittents, perform the
following steps:
1. Observe history DTCs, DTC modes, and freeze
frame data.
2. Evaluate the symptoms and the conditions described
by the customer.3. Use a check sheet or other method to identify the
circuit or electrical system component.
4. Follow the suggestions for intermittent diagnosis
found in the service documentation.
Most Scan Tools, such as the Tech 2, have data-capturing
capabilities that can assist in detecting intermittents.
No Trouble Found
This condition exists when the vehicle is found to operate
normally. The condition described by the customer may
be normal. Verify the customer complaint against another
vehicle that is operating normally. The condition may be
intermittent. Verify the complaint under the conditions
described by the customer before releasing the vehicle.
1. Re-examine the complaint.
When the complaint cannot be successfully found or
isolated, a re-evaluation is necessary. The complaint
should be re-verified and could be intermittent as
defined in
Intermittents section, or could be normal.
2. Repair and verify.
After isolating the cause, the repairs should be made.
Validate for proper operation and verify that the
symptom has been corrected. This may involve road
testing or other methods to verify that the complaint
has been resolved under the following conditions:

Conditions noted by the customer.

If a DTC was diagnosed, verify a repair by
duplicating conditions present when the DTC was
set as noted in the Failure Records or Freeze
Frame data.
Verifying Vehicle Repair
Verification of the vehicle repair will be more
comprehensive for vehicles with OBD II system
diagnostics. Following a repair, the technician should
perform the following steps:
IMPORTANT:Follow the steps below when you verify
repairs on OBD II systems. Failure to follow these steps
could result in unnecessary repairs.
1. Review and record the Failure Records and the
Freeze Frame data for the DTC which has been
diagnosed (Freeze Frame data will only be stored for
an A or B type diagnostic and only if the MIL(ºCheck
Engineº lamp) has been requested).
2. Clear the DTC(S).
3. Operate the vehicle within conditions noted in the
Failure Records and Freeze Frame data.
4. Monitor the DTC status information for the DTC which
has been diagnosed until the diagnostic test
associated with that DTC runs.
General Service Information
OBD II Serviceablity Issues
With the introduction of OBD II diagnostics across the
entire passenger car and light-duty truck market in 1996,
illumination of the MIL (ªCheck Engineº lamp) due to a
non-vehicle fault could lead to misdiagnosis of the
vehicle, increased warranty expense and customer