1.0 INTRODUCTION
The procedures contained in this manual include
specifications, instructions, and graphics needed to
diagnose the PCM Powertrain System. The diag-
nostics in this manual are based on the failure
condition or symptom being present at time of
diagnosis.
Please follow the recommendations below when
choosing your diagnostic path.
1. First make sure the DRBIIItis communicating
with the appropriate modules; ie., if the DRBIIIt
displays a ``No Response'' condition, you must
diagnose this first before proceeding.
2. Read DTC's (diagnostic trouble codes) with the
DRBIIIt.
3. If no DTC's are present, identify the customer
complaint.
4. Once the DTC or customer complaint is identi-
fied, locate the matching test in the Table of
Contents and begin to diagnose the symptom.
All component location views are in Section 8.0.
All connector pinouts are in Section 9.0. All system
schematics are in Section 10.0.
An * placed before the symptom description indi-
cates a customer complaint.
When repairs are required, refer to the appropri-
ate service manual for the proper removal and
repair procedure.
Diagnostic procedures change every year. New
diagnostic systems may be added; carryover sys-
tems may be enhanced. READ THIS MANUAL
BEFORE TRYING TO DIAGNOSE A VEHICLE
CODE. It is recommended that you review the
entire manual to become familiar with all new and
changed diagnostic procedures.
After using this book, if you have any comments
or recommendations, please fill out the form at the
back of the book and mail it back to us.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers the
following 2000 Chrysler Caravan Voyager vehicles
equipped with the 2.0L, 2.4L DOHC, 3.0L MPI,
3.3L/3.8L MPI, or 3.3L E85 compatible Engine.
1.2 SIX-STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the powertrain control module
(PCM) is done in six basic steps:
²verification of complaint
²verification of any related symptoms
²symptom analysis
²problem isolation
²repair of isolated problem
²verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
The Powertrain Control Module (PCM) monitors
and controls:
²Fuel system
²Ignition system
²charging system
²speed control system
²cooling system
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
3.1 GENERAL DESCRIPTION
These Sequential Fuel Injection (SFI) engine sys-
tems have the latest in technical advances. The
on-board Euro Stage III On-Board Diagnostic incor-
porated with the powertrain control module (PCM)
are intended to assist the field technician in repair-
ing vehicle problems by the quickest means.
3.2 FUNCTION OPERATION
3.2.1 FUEL CONTROL
The PCM controls the air/fuel ratio of the engine
by varying fuel injector on time. Mass air flow is
calculated using the speed density method using
engine speed, manifold absolute pressure, and air
temperature change.
Different fuel calculation strategies are used de-
pendent on the operational state of the engine.
During crank mode, a prime shot fuel pulse is
delivered followed by fuel pulses determined by a
crank time strategy. Cold engine operation is deter-
mined via an open loop strategy until the O2
sensors have reached operating temperature. At
this point, the strategy enters a closed loop mode
where fuel requirements are based upon the state of
the O2 sensors, engine speed, MAP, throttle posi-
tion, air temperature, battery voltage, and coolant
temperature.
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ProCarManuals.com
to non-emission codes, they will seem like an intermit-
tent. These codes require a set of parameters to be
performed (The DRBIIItpre-test screens will help
with this for MONITOR codes), this is called a ªTRIPº.
All EURO STAGE III OBD DTCs will be set after one
or in some cases two trip failures, and the MIL will be
turned on. These codes require three successful (no
failures) TRIPS to extinguish the MIL, followed by 40
warm-up cycles to erase the code.
3.3.2 INTERMITTENT CODE
A diagnostic trouble code that is not there every
time the PCM checks the circuit is an ªintermittentº
code. Most intermittent codes are caused by wiring
or connector problems. Defects that come and go
like this are the most difficult to diagnose; they
must be looked for under specific conditions that
cause them. The following checks may assist you in
identifying a possible intermittent problem:
²Visually inspect related wire harness connectors.
Look for broken, bent, pushed out, or corroded
terminals.
²Visually inspect the related harnesses. Look for
chafed, pierced, or partially broken wire.
²Refer to any Hotline Newsletters or technical
service bulletins that may apply.
²Use the DRBIIItdata recorder or co-pilot.
²Use the DRBIIItPEP module lab scope.
3.3.3 RESET COUNTER
The reset counter counts the number of times the
vehicle has been started since codes were last set,
erased, or the battery was disconnected. The reset
counter will count up to 255 start counts.
The number of starts helps determine when the
trouble code actually happened. This is recorded by
the PCM and can be viewed on the DRBIIItas
STARTS since set.
When there are no trouble codes stored in mem-
ory, the DRBIIItwill display ªNO DTC'S Detectedº
and the reset counter will show ªSTARTS since
clear = XXX.º
3.3.4 HANDLING NO TROUBLE CODE
PROBLEMS
Symptom checks cannot be used properly unless
the driveability problem characteristic actually
happens while the vehicle is being tested.
Select the symptom that most accurately de-
scribes the vehicle's driveability problem and then
perform the test routine that pertains to this symp-
tom. Perform each routine test in sequence until the
problem is found. For definitions, see Section 6.0
Glossary of Terms.SYMPTOM DIAGNOSTIC TEST
HARD START CHECKING THE 5-VOLT
SUPPLY CIRCUIT
CHECKING SECONDARY
IGNITION SYSTEM
CHECKING ENGINE VAC-
UUM
CHECKING THE FUEL
PRESSURE
CHECKING COOLANT SEN-
SOR CALIBRATION
CHECKING THROTTLE PO-
SITION SENSOR CALIBRA-
TION
CHECKING MAP SENSOR
CALIBRATION
CHECKING THE MINIMUM
IDLE AIR FLOW
CHECKING IDLE AIR CON-
TROL MOTOR OPERATION
CHECKING ENGINE ME-
CHANICAL SYSTEMS
CHECKING EVAP EMISSION
SYSTEM
CHECKING EGR SYSTEM
CHECKING IAT SENSOR
START AND
STALLCHECKING THE 5-VOLT
SUPPLY CIRCUIT
CHECKING SECONDARY
IGNITION SYSTEM
CHECKING PCM POWER
AND GND CKT
CHECKING THE FUEL
PRESSURE
CHECKING COOLANT SEN-
SOR CALIBRATION
CHECKING THROTTLE PO-
SITION SENSOR CALIBRA-
TION
CHECKING MAP SENSOR
CALIBRATION
CHECKING THE MINIMUM
IDLE AIR FLOW
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GENERAL INFORMATION
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CHECKING FOR OXYGEN
SENSOR SWITCHING
CHECKING O2S HEATER
CHECKING IDLE AIR CON-
TROL MOTOR OPERATION
CHECKING ENGINE ME-
CHANICAL SYSTEMS
CHECKING EVAP EMISSION
SYSTEM
CHECKING EGR SYSTEM
CHECKING IAT SENSOR
CHECKING PNP SWITCH
3.4 USING THE DRBIIIT
Refer to the DRBIIItuser 's guide for instructions
and assistance with reading trouble codes, erasing
trouble codes, and other DRBIIItfunctions.
3.5 DRB ERROR MESSAGES AND BLANK
SCREEN
Under normal operation, the DRBIIItwill dis-
play one of only two error messages:
± User-Requested WARM Boot or User-
Requested COLD Boot.
This is a sample of such an error message display:
ver: 2.14
date: 26 Jul93
file: key_itf.cc
date: Jul 26 1993
line: 548
err: 0x1
User-Requested COLD Boot
Press MORE to switch between this display
and the application screen.
Press F4 when done noting information.
3.5.1 DRB IIITDOES NOT POWER UP
If the LED's do not light or no sound is emitted at
start up, check for loose cable connections or a bad
cable. Check the vehicle battery voltage (data link
connector cavity 16). A minimum of 11 volts is
required to adequately power the DRBIIIt.
If all connections are proper between the
DRBIIItand vehicle or other devices, and the
vehicle battery is fully charged, an inoperative
DRBIIItmay be the result of a faulty cable or
vehicle wiring. For a blank screen, refer to the
appropriate body diagnostics manual.
3.5.2 DISPLAY IS NOT VISIBLE
Low temperatures will affect the visibility of the
display. Adjust the contrast to compensate for this
condition.
4.0 DISCLAIMERS, SAFETY,
WARNINGS
4.1 DISCLAIMERS
All information, illustrations, and specifications
contained in this manual are based on the latest
information available at the time of publication.
The right is reserved to make changes at any time
without notice.
4.2 SAFETY
4.2.1 TECHNICIAN SAFETY INFORMATION
WARNING: ENGINES PRODUCE CARBON
MONOXIDE THAT IS ODORLESS, CAUSES
SLOWER REACTION TIME, AND CAN LEAD
TO SERIOUS INJURY. WHEN THE ENGINE IS
OPERATING, KEEP SERVICE AREAS WELL
VENTILATED OR ATTACH THE VEHICLE
EXHAUST SYSTEM TO THE SHOP EXHAUST
REMOVAL SYSTEM.
Set the parking brake and block the wheels before
testing or repairing the vehicle. It is especially impor-
tant to block the wheels on front-wheel drive vehicles;
the parking brake does not hold the drive wheels.
When servicing a vehicle, always wear eye pro-
tection, and remove any metal jewelry such as
watchbands or bracelets that might make an inad-
vertent electrical contact.
When diagnosing a powertrain system problem,
it is important to follow approved procedures where
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GENERAL INFORMATION
ProCarManuals.com
applicable. These procedures can be found in ser-
vice manual procedures. Following these proce-
dures is very important to the safety of individuals
performing diagnostic tests.
4.2.2 VEHICLE PREPARATION FOR
TESTING
Make sure the vehicle being tested has a fully
charged battery. If it does not, false diagnostic codes
or error messages may occur.
4.2.3 SERVICING SUB-ASSEMBLIES
Some components of the powertrain system are
intended to be serviced in assembly only. Attempt-
ing to remove or repair certain system sub-
components may result in personal injury and/or
improper system operation. Only those components
with approved repair and installation procedures in
the service manual should be serviced.
4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRB MULTIMETER IS DANGEROUS. IT CAN
EXPOSE YOU TO SERIOUS INJURY.
CAREFULLY READ AND UNDERSTAND THE
CAUTIONS AND THE SPECIFICATION
LIMITS.
Follow the vehicle manufacturer 's service specifi-
cations at all times.
²Do not use the DRBIIItif it has been damaged.
²Do not use the test leads if the insulation is
damaged or if metal is exposed.
²To avoid electrical shock, do not touch the test
leads, tips or the circuit being tested.
²Choose the proper range and function for the
measurement. Do not try voltage or current mea-
surements that may exceed the rated capacity.
²Do not exceed the limits shown in the table below:
FUNCTION INPUT LIMIT
Volts 0 - 500 peak volts AC
0 - 500 volts DC
Ohms (resistance)* 0 -1.12 megohms
Frequency Measured
Frequency Generated0-10kHz
Temperature -58 - 1100ÉF
-50 - 600ÉC
* Ohms cannot be measured if voltage is present.
Ohms can be measured only in a non-powered
circuit.
²Voltage between any terminal and ground must
not exceed 500v DC or 500v peak AC.
²Use caution when measuring voltage above 25v
DC or 25v AC.
²The circuit being tested must be protected by a
10A fuse or circuit breaker.
²Use the low current shunt to measure circuits up
to 10A. Use the high current clamp to measure
circuits exceeding 10A.
²When testing for the presence of voltage or cur-
rent, make sure the meter is functioning cor-
rectly. Take a reading of a known voltage or
current before accepting a zero reading.
²When measuring current, connect the meter in
series with the load.
²Disconnect the live test lead before disconnecting
the common test lead.
²When using the meter function, keep the DRB
away from spark plug or coil wires to avoid
measuring error from outside interference.
4.3 WARNINGS AND CAUTIONS
4.3.1 ROAD TEST WARNINGS
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: BEFORE ROAD TESTING A
VEHICLE, BE SURE THAT ALL
COMPONENTS ARE REASSEMBLED.
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRB SCREEN WHILE IN MOTION.
DO NOT HANG THE DRB FROM THE REAR
VIEW MIRROR OR OPERATE IT YOURSELF.
HAVE AN ASSISTANT AVAILABLE TO
OPERATE THE DRB.
4.3.2 VEHICLE DAMAGE CAUTIONS
Before disconnecting any control module, make
sure the ignition is ªoffº. Failure to do so could
damage the module.
When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation; this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
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4.3.3 ELECTRONIC PINION FACTOR
WARNING
The pinion factor must be set for all new trans-
mission control modules. If the pinion factor is not
set or if it is set incorrectly, any speed-related
accessories will not operate or will operate inaccu-
rately. This includes the speedometer, speed con-
trol, rolling door locks, and other devices that are
operated by the powertrain and body control mod-
ules. For instructions on setting the pinion factor,
see the appropriate transmission diagnostic man-
ual or the service manual.
5.0 RECOMMENDED TOOLS
AND EQUIPMENT
DRBIIIt(diagnostic readout box) scan tool
fuel pressure adapter (C-6631) or #6539
fuel pressure kit (C-4799-B) or #5069
fuel release hose (C-4799-1)
MinAir flow fitting #6457
jumper wires
ohmmeter
oscilloscope
vacuum gauge
voltmeter
12 volt test light minimum 25 ohms resistance
with probe #8382
CAUTION: A 12 VOLT TEST LIGHT SHOULD
NOT BE USED FOR THE FOLLOWING
CIRCUITS, DAMAGE TO THE POWERTRAIN
CONTROLLER WILL OCCUR.
²5 Volt Supply
²8 Volt Supply
²J1850 PCI Bus
²CCD Bus
²CKP Sensor Signal
²CMP Sensor Signal
²Vehicle Speed Sensor Signal
²O2 Sensor Signal
6.0 GLOSSARY OF TERMS
ABSantilock brake system
backfire,
popbackfuel ignites in either the intake or
the exhaust system
CKPcrank position sensor
CMPcamshaft position sensor
cuts out,
missesa steady pulsation or the inability of
the engine to maintain a consistent
rpmDLCdata link connector (previously
called ªengine diagnostic connectorº)
detona-
tion,
spark
knocka mild to severe ping, especially un-
der loaded engine conditions
ECTengine coolant temperature sensor
EGRexhaust gas recirculation valve and
system
genera-
torpreviously called ªalternatorº
hard
startThe engine takes longer than usual
to start, even though it is able to
crank normally.
hesita-
tion, sag,
stumble
There is a momentary lack of response
when the throttle is opened.
This can
occur at all vehicle speeds. If it is se-
vere enough, the engine may stall.
IATintake air temperature sensor
IACidle air control valve
JTECCombined engine and transmission
control module
lack of
power,
sluggish
The engine has less than expected
power, with little or no increase in vehi-
cle speed when the throttle is opened.
LDPLeak Detection Pump
MAPmanifold absolute pressure sensor
MILmalfunction indicator lamp
MTVmanifold tuning valve
O2Soxygen sensor
PCIProgrammable Communication In-
terface
PCMpowertrain control module
PCMpowertrain control module
PCVpositive crankcase ventilation
PEPPeripheral Expansion Port
poor fuel
economyThere is significantly less fuel mile-
age than other vehicles of the same
design and configuration
rough,
unstable,
or er-
ratic idle
stallingThe engine runs unevenly at idle
and causes the engine to shake if it
is severe enough. The engine idle
rpm may vary (called ªhuntingº).
This condition may cause stalling if
it is severe enough.
SKIMSentry Key Immobilizer Module
SKISSentry Key Immobilizer System
start and
stallThe engine starts but immediately
dies.
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ProCarManuals.com
TEST ACTION APPLICABILITY
8 Ignition On, Engine Not Running.
With the DRB, read codes.
With the DRB, actuate the Evap Purge Solenoid.
Wiggle Wiring Harness from the Solenoid to PCM.
Does the Evap Purge Solenoid Control Circuit code return?ALL
Ye s®Repair as necessary where wiggling caused problem to appear.
Perform Powertrain Verification Test VER-5A.
No®Go To 9
9 Ignition Off.
Using the Schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?ALL
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 10
10 Check the freeze frame data to determine the conditions when code was set.
Attempt duplication of 'freeze frame' conditions for added diagnostics.
If there are no other possible causes remaining there is assumed to be an9intermit-
tent9problem with a Wiring Harness Connector or Wire.
View repair options.ALL
Repair
Visually inspect related Wire Harness Connectors and Harnesses.
Look for broken, bent, pushed out, or corroded terminals and for
chafed, pierced, or partiallly broken wire, respectively. Refer to
any hotlines or technical service bulletins that apply.
11 Ignition On, Engine Not Running.
With the DRB, actuate the Evap Purge Solenoid.
With the DRB, read codes.
Is the Global Good Trip displayed and equal to 0?ALL
Ye s®Go To 12
No®Go To 18
12 Ignition Off.
Disconnect Proportional Purge Solenoid Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the Proportional Purge Solenoid.
Is the resistance 14.2 ohms +/- 1.4?ALL
Ye s®Go To 13
No®Replace the open Proportional Purge Solenoid.
Perform Powertrain Verification Test VER-5A.
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DRIVEABILITY
P-0443 EVAP PURGE SOLENOID CIRCUIT ÐContinued
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TEST ACTION APPLICABILITY
16 Ignition Off.
Disconnect Proportional Purge Solenoid Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the battery.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Powertrain Control Module.
Note: Check connectors - Clean/repair as necessary.
Using and Ohmmeter, measure the PWM Purge Sense Circuit PCM to Solenoid
Connector.
Is the resistance below 5.0 ohms?ALL
Ye s®Go To 17
No®Repair the open PWM Purge Sense Circuit.
Perform Powertrain Verification Test VER-5A.
17 If there are no potential causes remaining, the Powertrain Control Module is
assumed to be defective.
View repair options.ALL
Repair
Replace the Powertrain Control Module.
Perform Powertrain Verification Test VER-5A.
18 Ignition On, Engine Not Running.
With the DRB, actuate the Evap Purge Solenoid.
With the DRB, read codes.
Wiggle Wiring Harness from the Solenoid to PCM.
Does the Evap Purge Solenoid Control Circuit code return?ALL
Ye s®Repair as necessary where wiggling caused problem to appear.
Perform Powertrain Verification Test VER-5A.
No®Go To 19
19 Ignition Off.
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?ALL
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 20
20 Check the freeze frame data to determine the conditions when code was set.
Attempt duplication of 'freeze frame' conditions for added diagnostics.
If there are no other possible causes remaining there is assumed to be an9intermit-
tent9problem with a Wiring Harness Connector or Wire.
View repair options.ALL
Repair
Visually inspect related Wire Harness Connectors and Harnesses.
Look for broken, bent, pushed out, or corroded terminals and for
chafed, pierced, or partiallly broken wire, respectively. Refer to
any hotlines or technical service bulletins that apply.
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DRIVEABILITY
P-0443 EVAP PURGE SOLENOID CIRCUIT ÐContinued
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TEST ACTION APPLICABILITY
4 Check the freeze frame data to determine the conditions when code was set.
Attempt duplication of 'freeze frame' conditions for added diagnostics.
If there are no other possible causes remaining there is assumed to be an9intermit-
tent9problem with a Wiring Harness Connector or Wire.
View repair options.All
Repair
Visually inspect related Wire Harness Connectors and Harnesses.
Look for broken, bent, pushed out, or corroded terminals and for
chafed, pierced, or partiallly broken wire, respectively. Refer to
any hotlines or technical service bulletins that apply.
5 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Key on.
Using a Voltmeter, measure the voltage of the Fused Ignition Switch Output Circuit
at the Solenoid Connector.
Is the voltage above 10.0 volts?All
Ye s®Go To 6
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-6A.
6 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Disconnect the PCM.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the LDP Solenoid Control Circuit at
the PCM Connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the LDP Solenoid Circuit for a short to ground.
Perform Powertrain Verification Test VER-6A.
No®Go To 7
7 Ignition Off
Disconnect the LDP Solenoid.
Note: Check connectors - Clean/repair as necessary.
Disconnect the PCM.
Note: Check connectors - Clean/repair as necessary.
With an Ohmmeter, measure the resistance of the LDP Solenoid Control Circuit from
the PCM Connector to the LDP Connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair the open LDP Solenoid Control Circuit.
Perform Powertrain Verification Test VER-6A.
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DRIVEABILITY
P-1495 LEAK DETECTION PUMP SOLENOID CIRCUIT ÐContinued
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