
6E±506
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Symptom Diagnosis
Preliminary Checks
Before using this section, perform the ªOn-Board
Diagnostic (OBD) System Checkº and verify all of the
following items:
The powertrain control module (PCM), and
malfunction indicator lamp (MIL) (Check Engine
lamp) and Reduced Power Lamp (RPL) are operating
correctly.
There are no DTC(s) stored.
Tech 2 data is within normal operating range. Refer to
Typical Scan Data Values.
Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
Visual/Physical Check
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time.
This check should include the following items:
PCM grounds for cleanliness, tightness and proper
location.
Vacuum hoses for splits, kinks, and proper
connections, as shown on the ªVehicle Emission
Control Informationº label. Check thoroughly for any
type of leak or restriction.
Air intake ducts for collapsed or damaged areas.
Air leaks at throttle body mounting area, mass air flow
(MAF) sensor and intake manifold sealing surfaces.
Ignition components for cracking, hardness, and
carbon tracking.
Wiring for proper connections, pinches and cuts.
Intermittents
IMPORTANT:An intermittent problem may or may not
turn on the malfunction indicator lamp (MIL) or store a
DTC. DO NOT use the Diagnostic Trouble Code (DTC)
charts for intermittent problems. The fault must be
present to locate the problem.
Most intermittent problems are caused by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions:
Poor mating of the connector halves or a terminal not
fully seated in the connector (backed out).
Improperly formed or damaged terminal.
All connector terminals in the problem circuit should
be carefully checked for proper contact tension.
Poor terminal-to-wire connection. This requires
removing the terminal from the connector body to
check.
Road test the vehicle with a J 39200 Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Use a Tech 2 to help detect intermittent conditions. The
scan tool has several features that can be used to locatean intermittent condition. Use the following feature to find
intermittent faults:
Using a Tech 2's ªFreeze Frameº buffer or ªFailure
Recordsº buffer can aid in locating an intermittent
condition. Review and record the information in the
freeze frame or failure record associated with the
intermittent DTC being diagnosed. The vehicle can
be driven within the conditions that were present
when the DTC originally set.
To check for loss of diagnostic code memory, disconnect
the MAP sensor and idle the engine until the MIL (Check
Engine lamp) comes on. DTC P0107 should be stored
and kept in memory when the ignition is turned ªOFFº. If
not, the PCM is faulty. When this test is completed, make
sure that you clear the DTC P0107 from memory.
An intermittent MIL (Check Engine lamp) with no stored
DTC may be caused by the following:
Ignition coil shorted to ground and arcing.
MIL (Check Engine lamp) wire to PCM shorted to
ground.
Poor PCM grounds. Refer to the PCM wiring
diagrams.
Check for improper installation of electrical options such
as lights, cellular phones, etc. Check all wires from the
PCM to the ignition coils for poor connections.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in
Electrical Diagnosis).
If problem has not been found, refer to
PCM Connector
Symptom
tables.
Check the ªCalibration IDº of the PCM, and compare it
with the latest Isuzu service bulletins and/or Isuzu
EEPROM reprogramming equipment to determine if
an update to the PCM's reprogrammable memory
has been released. To check the ªCalibration IDº,
connect the Tech 2, then look for ªPowertrainº, then
select ªCalibration IDº. This identifies the contents of
the reprogrammable software and calibration
contained in the PCM. If the ªCalibration IDº is not the
most current available, it is advisable to reprogram
the PCM's EEPROM memory, which may either help
identify a hard-to-find problem or may fix the problem.
Calibration ID (example)
Part number 9377709
Broadcast Code CYYD
Identifier 801

6E±545
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Malfunction Indicator Lamp
(MIL)
Removal and Installation Procedure
Refer to Warning light bulb, indicator light valve,
illumination light bulb, A/T indicator light bulb in Meter and
Gauge.
Reduced Power Lamp
The reduced power lamp (RPL) turns on when the ignition
key is moved to the ON position. It should turn off in
approximately 3 seconds or immediately after the engine
starts.
If the RPL turns on during vehicle operation, a vehicle
system failure resulting in reduced engine output is
indicated.
If both the reduced RPL and the check engine light turn
on, a serious problem affecting vehicle performance is
indicated.
Refer to the
OBD system check NO and RPL ªONº steady
in this manual.
Powertrain Control Module
(PCM)
Service Precaution
NOTE: To p r e ve n t p ossible electrostatic discharge
damage to the PCM, do not touch the connector pins or
soldered components on the circuit board.
Electrostatic Discharge (ESD)
Damage
Electronic components used in the control systems are
often designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. Less than 100 volts of static
electricity can cause damage to some electronic
components. By comparison, it takes as much as 4,000
volts for a person to even feel the zap of a static
discharge.
There are several ways for a person to become statically
charged. The most common methods of charging are by
friction and by induction. An example of charging by
friction is a person sliding across a car seat.
Charging by induction occurs when a person with well
insulated shoes stands near a highly charged object and
momentarily touches ground. Charges of the same
polarity are drained off leaving the person highly charged
with the opposite polarity. Static charges can cause
damage, therefore, it is important to use care when
handling and testing electronic components.
NOTE: To prevent possible Electrostatic Discharge
damage, follow these guidelines:
Do not touch the control module connector pins or
soldered components on the control module circuit
board.Do not open the replacement part package until the
part is ready to be installed.
Before removing the part from the package, ground
the package to a known good ground on the vehicle.
If the part has been handled while sliding across the
seat, or while sitting down from a standing position, or
while walking a distance, touch a known good ground
before installing the part.
NOTE: To prevent internal PCM damage, the ignition
must be in the ªOFFº position in order to disconnect or
reconnect power to the PCM (for example: battery cable,
PCM pigtail, PCM fuse, jumper cables, etc.).
IMPORTANT:When replacing the production PCM
with a service PCM, it is important to transfer the
broadcast code and production PCM number to the
service PCM label. This will allow positive identification of
PCM parts throughout the service life of the vehicle. Do
not record this information on the metal PCM cover.
IMPORTANT:The ignition should always be in the
ªOFFº position in order to install or remove the PCM
connectors.
Service of the PCM should normally consist of either re-
placement of the PCM or EEPROM programming. If the
diagnostic procedures call for the PCM to be replaced,
the PCM should be checked first to ensure it is the correct
part. If it is, remove the faulty PCM and install the new
service PCM.
The service PCM EEPROM will not be programmed.
DTC P0601 indicates the check sum error.
Removal Procedure
1. Disconnect the negative battery cable.
2. Block the wheels.
3. Remove the two screws from the PCM electrical
connectors.
4. Disconnect the PCM electrical connectors.
060RY00065

7A±12
AUTOMATIC TRANSMISSION (4L30±E)
Mechanical / Hydraulic Diagnosis Check Trans Indicator Chart
Perform Preliminary Inspection First!
F07RT013
When the ªCHECK TRANSº indicator is flashing, it
indicates that a problem related to the transmission, the
Powertrain Control Module (PCM), or the vehicle harness
has occurred.
The system is now operating in a ªBACKUP MODEº
where the risk of further damaging the transmission has
been reduced. The vehicle may be shifted manually.
If the initial problem is intermittent or seldom, switching
the engine OFF/ON might allow normal operation again
until the problem reoccurs.

8A±22LIGHTING SYSTEM
Light NameBulb No.Rated
PowerNumber of
BulbsLens ColorRemarks
Headlight9005/900660w/51w2WhiteHalogen
Front Turn signal Light/
Front Side Marker Light/Parking Light1157NA27w/8w2Amber
Rear Turn Signal Light744021w2Amber
Backup Light92118w2White
Taillight/Stoplight744321w/5w2Red
High Mounted Stoplight92118w2Red
License Plate Light (Tailgate type)1685w2White
Map LightÐ8w2White
Dome LightÐ10w1White
Luggage Room LightÐ5w1White
Courtesy LightÐ3.4w4White
Check TransÐ1.4w1RedMeter
A/T Oil TempÐ1.4w1RedMeter
Cruise SetÐ1.4w1GreenMeter
Power DriveÐ1.4w1AmberMeter
Winter DriveÐ1.4w1GreenMeter
Turn SignalÐ1.4w2GreenMeter
Check TODÐ1.4w1RedMeter
High BeamÐ1.4w1BlueMeter
ABSÐ1.4w1AmberMeter
Seat BeltÐ2w1RedMeter
Indicator/Warning
Malfunction Indicator
(Check Engine)Ð1.4w1AmberMeter
Indicator/Warning
LightLow FuelÐ1.4w1AmberMeterg
Reduced PowerÐ1.4w1AmberMeter
Sports ModeÐ1.4w1GreenMeter
TOD FrontÐ1.1w1GreenMeter
TOD AutoÐ1.1w1GreenMeter
TOD RearÐ1.1w1GreenMeter
Oil PressureÐ1.4w1RedMeter
Brake SystemÐ1.4w1RedMeter
ChargeÐ1.4w1RedMeter
A/T Shift PositionÐ1.1w7
P,N,D,3,2,L
:Green
R: Amber
Meter
Air BagÐ2w1RedMeter
Illumination LightMeterÐ3.4w4Meter
Shift leverÐ1.4w1WhiteShift lever
Vanity MirrorÐ2w2WhiteSun Visor
Cigarette LighterÐ1.4w1WhiteCigarette
Lighter
AshtrayÐ1.4w1WhiteAshtray

METER AND GAUGE8E±5
Connector A
TerminalFunction
1Ð
2Intelligent suspension indicator light
3TOD indicator light ªRearº
4Ð
5TOD indicator light ªAUTOº
6Ð
7TOD indicator light ªFrontº
8A/T shift indicator light ª3º
9A/T shift indicator light ªDº
10A/T shift indicator light ª2º
11SRS ± air bag warning light
12Ground
13Battery
14Stater switch
15A/T oil temperature warning light
16Seat belt indicator light
17Charge warning light
18Ð
19Ð
20Ð
21A/T shift indicator light ªLº
22ABS warning light
23Ð
24Ð
25Reduced power warning light
26Oil pressure warning light
27Check trans warning light
28MIL(check engine) warning light
29Check TOD
30Engine coolant temperature gauge
Connector B
TerminalFunction
1A/T shift indicator light ªRº
2A/T shift indicator light
3A/T shift indicator light ªNº
4A/T shift indicator light ªPº
5Illumination light
6Engine revolution pulse
7Speed sensor pulse
8Turn signal indicator light (LH)
9Brake warning light
10High beam indicator light (+)
11High beam indicator light (±)
12Turn signal indicator light (RH)
13Turn signal indicator light
14Ð
15Illumination light
16Ground
Connector C
TerminalFunction
1Starter switch
2Ð
3Fuel gauge
4Low fuel warning light
5Cruise set indicator light
6Ð
7Ð
8Ð
9Ð
10Sport mode indicator light
11Ð
12Winter drive indicator light
13Power drive indicator light
14Ð