key battery ISUZU AXIOM 2002 Service Repair Manual

5A±39
BRAKE CONTROL SYSTEM
Chart B-1 With the key in the ON position (Before starting the engine). Warning light (W/L)
is not activated.
StepActionYe sNo
1Is W/L fuse disconnected?Replace fuse.
Go to
Step 5Go to Step 2
2Is W/L burnt out?Replace W/L
bulb.
Go to
Step 5Go to Step 3
31. Turn the key off.
2. Disconnect coil integrated module connector (C-6).
3. Turn the key ON.
Is the check voltage between coil integrated module connector
(C-6) terminals 6 and 7 the battery voltage?
Go to Step 4
Repair harness
and connector.
Go to
Step 5
4Is there the continuity between coil integrated module connector
(C-6) terminals, 1 and 7 and body ground.Check harness
for suspected
disconnection
No fault found:
Replace EHCU.
Go to
Step 5
Repair harness
and connector.
Go to
Step 5
5Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the ªBasic
diagnostic flow
chartº
Go to Step 5
Chart B-2 CPU Error (DTC 14 (Flash out) / C0271, C0272, C0273, C0284 (Serial
communications))
StepActionYe sNo
11. Turn the key off.
2. Disconnected coil integrated module connector.
3. Inspect coil integrated module ground.
Is there the continuity between the coil integrated module
connector terminals, 2 (C-5) and 7 (C-6) and body ground?
Go to Step 2
Repair the body
ground harness.
Go to
Step 3
21. Turn the key off, connect the coil integrated module connector.
2. Erase the trouble code.
3. Turn Ignition off, then on, to perform system self-check.
4. If warning light remains on, display trouble codes once again.
Is the trouble code the DTC 14 (Flash out) / C0271, C0272,
C0273, C0284 (Serial communications)?
Replace EHCU.
Go to
Step 3
Inspect in
accordance with
the DTC
displayed.
31. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3

5A±40BRAKE CONTROL SYSTEM
Chart B-3 Low or High Ignition Voltage (DTC 15 (Flash out) / C0277, 0278 (Serial
communications))
StepActionYe sNo
1Is the battery voltage normal? (Battery capacity check)
Go to Step 2
Charge or
replace battery.
Go to
Step 2
21. Turn the key off.
2. Disconnect coil integrated module connector.
3. Turn the key on.
Is the voltage between coil integrated module connector (C-6)
terminals 1 and 7, higher than 10V?Check harness
connector for
suspected
disconnection
Fault found:
Repair, and
perform system
self-check
No fault found:
replace EHCU.
Go to
Step 3
Repair harness or
connector.
Go to
Step 3
31. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3
Chart B-4 Excessive Dump Time (DTC 17 (Flash out) / C0269 (Serial communications))
StepActionYe sNo
1Check for anything causing extended ABS activation, such as
locked brakes or an erratic speed sensor signal.
Was a problem found?
Repair or
Replace
Go to Step 2
21. The key turned off.
2. Replace EHCU.
3. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 2
Chart B-5 Excessive Isolation Time (DTC 18 (Flash out) / C0274 (Serial communications))
StepActionYe sNo
1Check for anything causing extended ABS activation, such as
locked brakes or an erratic speed sensor signal.
Was a problem found?
Repair or
Replace
Go to Step 2
21. The key turned off.
2. Replace EHCU.
3. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 2

5A±41
BRAKE CONTROL SYSTEM
Chart B-6 G-Sensor Output Failure (DTC 21 (Flash out) / C0276 (Serial communications))
StepActionYe sNo
11. Turn the key off.
2. Replace EHCU.
3. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 1
Chart B-7 Brake Switch Failure (DTC 22 (Flash out) / C0281 (Serial communications))
StepActionYe sNo
1Is the stop light actuated when the brake pedal is depressed?Go to Step 2Go to Step 4
21. Turn the key off.
2. Disconnected coil integrated module connector.
Is the check voltage between coil integrated module connector
(C-6) terminals 13 to 7 when brake pedal is depressed the battery
voltage?
Go to Step 3
Harness between
brake SW and
coil integrated
module is faulty.
Go to
Step 6
3Is the check that pins C-5 connector 2, and C-6 connector 7 have
good ground?Check harness /
connector for
disconnection
Fault found:
Repair, and
perform system
self-check.
No fault found:
replace EHCU.
Go to
Step 6
Repair.
Go to
Step 6
4Is stop light fuse normal?
Go to Step 5
Replace.
Go to
Step 6
5Is brake SW normal?Abnormal
harness in stop
light circuit.
Repair the
harness.
Go to
Step 6
Replace.
Go to
Step 6
61. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 6

5A±42BRAKE CONTROL SYSTEM
Chart B-8 2WD Controller in 4WD Vehicle Controller (DTC 13 (Flash out) / C0285 (Serial
communications)), 4WD State Input Signal Failure (DTC 24 (Flash out) / C0282 (Serial
communications))
StepActionYe sNo
1Remove coil integrated module connector.
Is the coil integrated module connector (C-6) terminal 8 line
normally?
Go to Step 2
Repair.
Go to
Step 3
2Is the TOD control unit normally?
Replace EHCU.
Go to
Step 3
Replace TOD
control unit.
Go to
Step 3
31. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3
Chart B-9 Pump Motor Failure (DTC 32 (Flash out) / C0267, C0268 (Serial
communications))
StepActionYe sNo
11. Turn the key off.
2. Disconnect coil integrated module connector.
3. Measure the voltage between terminal 1 of the coil integrated
module connector (C-5) and body ground.
Is the voltage equal to the battery voltage?
Go to Step 2
Repair
fuse/harness
between battery
and coil
integrated
module connector
(C-5) terminal 1.
Go to
Step 5
2Is the harness from the hydraulic unit connected to the coil
integrated module connector?
Go to Step 3
Connect to the
connector.
Go to
Step 3
3Is the hydraulic unit harness in good condition?
Go to Step 4
Replace EHCU.
Go to
Step 5
4Is the resistance of hydraulic unit connector terminals 1 and 2
between 0.2 and 1.0 ohms?Replace EHCU.
Go to
Step 5
Replace EHCU.
Go to
Step 5
51. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 5

5A±43
BRAKE CONTROL SYSTEM
Chart B-10 EHCU Valve Relay Failure (DTC 35 (Flash out) / C0265, C0266 (Serial
communications))
StepActionYe sNo
11. Turn the key off.
2. Disconnect coil integrated module connector.
3. Measure the voltage between terminal 1 of the coil integrated
module connector (C-5) and body ground.
Is the voltage equal to the battery voltage?
Replace EHCU.
Go to
Step 2
Repair fuse and
harness between
coil integrated
module connector
(C-5) terminal 1
and battery.
Go to
Step 2
21. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 2
Chart B-11 FL Isolation Solenoid Coil Failure (DTC 41 (Flash out) / C0245, C0247 (Serial
communications))
StepActionYe sNo
1Was the ªEHCU Connector Pin±out Checksº performed?
Go to Step 2
Go to ªEHCU
Connector
Pin±out Checks.º
21. Turn the key switch to off.
2. Disconnect the 2±way EHCU connector (C±5) from the
EHCU.
3. Inspect the connector for damage or corrosion.
Is the connector free from damage or corrosion?
Go to Step 3
Repair the
connector.
Repeat the ªBasic
Diagnostic Flow
Chart.º
31. Replace the Coil Integrated Module.
2. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3
Chart B-12 FL Dump Solenoid Coil Failure (DTC 42 (Flash out) / C0246, C0248 (Serial
communications))
StepActionYe sNo
1Was the ªEHCU Connector Pin±out Checksº performed?
Go to Step 2
Go to ªEHCU
Connector
Pin±out Checks.º
21. Turn the key switch to off.
2. Disconnect the 2±way EHCU connector (C±5) from the
EHCU.
3. Inspect the connector for damage or corrosion.
Is the connector free from damage or corrosion?
Go to Step 3
Repair the
connector.
Repeat the ªBasic
Diagnostic Flow
Chart.º
31. Replace the Coil Integrated Module.
2. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?
Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3

6C±9 ENGINE FUEL (6VE1 3.5L)
NOTE: Do not use tools of any kind. Only use bare hands
when disconnecting the connector. Use a lubricant (light
oil) and/or push and pull the connector until the pipe is
disconnected.
Cover the connectors that was removed with a plastic
bag, to prevent dust or rain water from entering.
140R100028
Reuse of Quick±Connector

Replace the port and connector if scratch, dent or
crack is found.

Remove any dirt build up on the port when installing
the connector. Replace the connector, if there is any
forms of rust, dent, scratch.

After cleaning the port, insert it straight into the
connector until it clicks. After it clicks, try pulling it out
to make sure that it is not drawn and is securely
locked.
140R100036
Assembling Advice
By applying engine oil or light oil to the pipe, port makes
pipe assembly easier. The pipe assembly should take
place immediately after applying oil (to prevent dust from
sticking to the pipe surface ± which may decrease sealing
ability).
Test/Inspection After Assembling
1. Reconnect the battery negative cable.
2. Turn the ignition key to the ªONº position and listen for
pump start-up sound. Inspect for leaks, the fuel
pressure will increase as the fuel pump is actuated.
3. Perform leak inspection (step 2) several times.
4. Start the engine and observe the engine idle speed.
The presence of dirt in the fuel system may affect the
fuel injection system.

6E±39
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Identifying stored Diagnostic Trouble Codes (DTCs).

Clearing DTCs.

Performing output control tests.

Reading serial data.
TS24064
Decimal/Binary/Hexadecimal Conversions
Beginning in 1996, Federal Regulations require that all
auto manufacturers selling vehicles in the United States
provide Scan Tool manufacturers with software
information to display vehicle operating parameters. All
Scan Tool manufacturers will display a variety of vehicle
information which will aid in repairing the vehicle. Some
Scan Tools will display encoded messages which will aid
in determining the nature of the concern. The method of
encoding involves the use of a two additional numbering
systems: Binary and Hexadecimal.
The binary number system has a base of two numbers.
Each digit is either a 0 or a 1. A binary number is an eight
digit number and is read from right to left. Each digit has a
position number with the farthest right being the 0 position
and the farthest left being the 7 position. The 0 position,
when displayed by a 1, indicates 1 in decimal. Each
position to the left is double the previous position and
added to any other position values marked as a 1.
A hexadecimal system is composed of 16 different alpha
numeric characters. The alpha numeric characters used
are numbers 0 through 9 and letters A through F. The
hexadecimal system is the most natural and common
approach for Scan Tool manufacturers to display data
represented by binary numbers and digital code.
Verifying Vehicle Repair
Verification of vehicle repair will be more comprehensive
for vehicles with OBD II system diagnostic. Following a
repair, the technician should perform the following steps:
1. Review and record the Fail Records and/or 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 has been
requested).
2. Clear DTC(s).
3. Operate the vehicle within conditions noted in the Fail
Records and/or 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.
Following these steps are very important in verifying
repairs on OBD ll systems. Failure to follow these steps
could result in unnecessary repairs.
Reading Diagnostic Trouble Codes Using
The Tech 2 Scan Tool
The procedure for reading diagnostic trouble code(s) is to
use a diagnostic Scan Tool. When reading DTC(s), follow
instructions supplied by tool manufacturer.
Clearing Diagnostic Trouble Codes
IMPORTANT:Do not clear DTCs unless directed to do
so by the service information provided for each diagnostic
procedure. When DTCs are cleared, the Freeze Frame
and Failure Record data which may help diagnose an
intermittent fault will also be erased from memory.
If the fault that caused the DTC to be stored into memory
has been corrected, the Diagnostic Executive will begin to
count the ªwarm-upº cycles with no further faults
detected, the DTC will automatically be cleared from the
PCM memory.
To clear Diagnostic Trouble Codes (DTCs), use the
diagnostic Scan Tool ªclear DTCsº or ªclear informationº
function. When clearing DTCs follow instructions
supplied by the tool manufacturer.
When a Scan Tool is not available, DTCs can also be
cleared by disconnecting
one of the following sources for
at least thirty (30) seconds.
NOTE: To prevent system damage, the ignition key must
be ªOFFº when disconnecting or reconnecting battery
power.

The power source to the control module. Examples:
fuse, pigtail at battery PCM connectors, etc.

The negative battery cable. (Disconnecting the
negative battery cable will result in the loss of other
on-board memory data, such as preset radio tuning).

6E±146
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0108 MAP Sensor Circuit High Voltage
060R200051
Circuit Description
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum). The
MAP sensor signal voltage to the powertrain control
module (PCM) varies from below 2 volts at idle (high
vacuum) to above 4 volts with the key ªONº, engine not
running or at wide-open throttle (low vacuum).
The MAP sensor is used to determine manifold pressure
changes while the linear EGR flow test diagnostic is being
run (refer to
DTC P0401), to determine engine vacuum
level for some other diagnostics and to determine
barometric pressure (BARO). The PCM monitors the
MAP signals for voltages outside the normal range of the
MAP sensor. If the PCM detects a MAP signal voltage
that is excessively high, DTC P0108 will be set.
Conditions for Setting the DTC

No TP sensor DTCs present.

Engine is running for more than 10 seconds.

Throttle position is below 3% if engine speed is below
1000 RPM.

Throttle position is below 10% if engine speed is above
1000 RPM.

The MAP sensor indicates an intermittent manifold
absolute pressure above 80 kPa for a total of
approximately 10 seconds over a 16-second period.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected fault.

The PCM will default to a BARO value of 79.3 kPa.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P0108 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0108 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:

The MAP sensor shares a 5 Volt reference with the
Fuel Tank Pressure Sensor (Vapor Pressure Sensor).
If these codes are also set, it could indicate a problem
with the 5 Volt reference circuit.

The MAP sensor shares a ground with the Fuel Tank
Pressure Sensor, the ECT sensor, and the
Transmission Fluid Temperature sensor.

Poor connection at PCM ± Inspect harness connectors
for backed-out terminals, improper mating, broken

6E±256
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0300 Engine Misfire Detected
Circuit Description
Misfire is monitored as a function of the combustion
quality (CQ) signals generated from the ION Sensing
Module. Combustion signals represent the degree of
combustion in each cylinder. Misfire is detected when the
combustion signal is below a predetermined value.
This DTC P0300 will determine if a multiple cylinder
misfire is occurring by monitoring the Combustion
Quality.
Conditions for Setting the DTC

None of the following DTCs occur: TP sensor, MAF
sensor, VSS, ECT sensor.

The engine speed is between 600 and 6250 RPM.

The system voltage is between 11 and 16 volts.

The engine temperature sensor (ECT) indicates an
engine temperature between ±7
C (20
F) and 110
C
(230
F).

Throttle angle is steady and throttle changes less than
2% per 125 milliseconds.
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected the fault.

If the misfire is severe enough to cause possible
catalyst damage, the PCM will flash the MIL for as long
as the misfire remains at catalyst damaging levels.

The PCM will disable the TCC operation.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle in which the diagnostic has been
run and the fault condition is no longer present.

A history DTC P0300 will clear after 40 consecutive
warm-up cycles occur without a fault.

DTC P0300 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
The Tech 2 display ªMisfire Cur. #1 through #6º can be
useful to determine whether the misfire is isolated to a
single cylinder.
Damaged or faulty ignition coil ± Check for cracks or
other damage.

Substitute a known good coil ± Swap the ignition coils
and retest. If the misfire follows the coil, replace the
ignition coil.
If the misfire is random, check for the following conditions:

System grounds ± Ensure all connections are clean
and properly tightened.

MAF ± A mass air flow (MAF) sensor output that
causes the PCM to sense a lower than normal air flow
will cause a lean condition.

Air induction system ± Air leaks into the induction
system which bypass the MAF sensor will cause a lean
condition. Check for disconnected or damaged
vacuum hoses, incorrectly installed or faulty PCV
valve, or for vacuum leaks at the throttle body, EGR
valve, and intake manifold mounting surfaces.

Fuel pressure ± Perform a fuel system pressure test.
A faulty fuel pump, plugged filter, or faulty fuel system
pressure regulator will contribute to a lean condition.

Injector(s) ± Perform an injector coil/balance test to
locate faulty injector(s) contributing to a lean or
flooding condition. In addition to the above test, check
the condition of the injector O-rings.

EGR ± Check for a leaking valve, adapter, or feed pipes
which will contribute to a lean condition or excessive
EGR flow.

Fuel quality ± Using fuel with the wrong octane rating
for the vehicle may cause driveability problems.
Although alcohol-enhanced fuels may raise the octane
rating, the fuel's ability to turn into vapor in cold
temperatures deteriorates. This may affect the cold
driveability of the engine. The Reid Vapor Pressure of
the fuel can also create problems in the fuel system,
especially during the spring and fall when changes by
the refineries may not coincide with changes in the
weather.

Vehicle marshalling ± The transportation of new
vehicles from the assembly plant to the dealership can
involve as many as 60 key cycles within 2 to 3 miles of
driving. This type of operation contributes to the fuel
fouling of the spark plugs and will turn on the MIL with
a P0300 Misfire DTC.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

6E±490
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1523 Actuator Control Return Performance
D06RY00111
Circuit Description

The throttle position (TP) sensor circuit provides a
voltage signal relative to throttle position (blade angle).
The throttle blade angle will vary from about 8 % at
closed throttle to about 92 % at wide open
throttle(WOT).

The DC motor circuit provides a voltage signal relative
to command throttle position (blade angle).

This DTC detects if the throttle return to the default
position at key on is steady.
Conditions for setting the DTC

The ignition is ªONº.

Normalized TPS is less than 7 % or Normalized TPS
is more than 25 %.
Action Taken When the DTC Sets

The PCM will not turn the malfunction indicator lamp
(MIL) ªONº.

The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.
A history DTC P1523 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1523 can be cleared using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
An intermittent may be caused by the following:

Poor connections.

Misrouted harness.

Rubbed through wire insulation.

Broken wire inside the insulation.
Check for the following conditions:

Poor connection at PCM-Inspect harness connectors
for backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
TP sensor 1, TP sensor 2 display on the Tech 2 while
moving connectors and wiring harnesses related to the
sensor.
A change in the display will indicate the location of
the fault. If DTC P1523 cannot be duplicated, the
information included in the Failure Records data can
be useful in determining vehicle mileage since the
DTC was last set.