
TABLE OF CONTENTS - Continued
AMBIENT TEMPERATURE SENSOR - BLACK 2 WAY........................291
AMBIENT TEMPERATURE SENSOR (SENSOR SIDE)-2WAY................292
BRAKE LAMP SWITCH - BLACK 6 WAY...................................292
BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID - BLACK 2 WAY.......292
CAMSHAFT POSITION SENSOR - BLACK 3 WAY...........................292
CLOCKSPRING C1 - WHITE 6 WAY.......................................292
CRANKSHAFT POSITION SENSOR - BLACK 3 WAY.........................293
DATA LINK CONNECTOR - WHITE 16 WAY................................293
DIAGNOSTIC JUNCTION PORT - BLACK 16 WAY...........................293
EGR SOLENOID - GRAY 2 WAY..........................................294
ENGINE COOLANT TEMPERATURE SENSOR - BLACK 2 WAY................294
ENGINE OIL PRESSURE SWITCH - LT. GREEN 2 WAY......................294
EVAP/PURGE SOLENOID - BLACK 2 WAY.................................294
FUEL INJECTOR NO. 1 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 2 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 3 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 4 - BLACK 2 WAY...................................295
FUEL INJECTOR NO. 5 (3.3L/3.8L) - BLACK 2 WAY..........................296
FUEL INJECTOR NO. 6 (3.3L/3.8L) - BLACK 2 WAY..........................296
FUEL TANK MODULE - LT. GRAY 4 WAY...................................296
GENERATOR - BLACK 2 WAY...........................................296
GENERATOR (GENERATOR SIDE).......................................297
MANIFOLD ABSOLUTE PRESSURE SENSOR - BLACK 3 WAY................297
OXYGEN SENSOR 1/1 UPSTREAM - BLACK 4 WAY.........................297
OXYGEN SENSOR 1/2 DOWNSTREAM - BLACK 4 WAY.....................297
FUSES (IPM)..........................................................299
A/C COMPRESSOR CLUTCH RELAY......................................299
ACCESSORY RELAY...................................................299
AUTOMATIC SHUTDOWN RELAY........................................300
ENGINE STARTER MOTOR RELAY.......................................300
FUEL PUMP RELAY....................................................300
POSITIVE TEMPERATURE COEFFICIENTS................................300
TRANSMISSION SAFETY SHUTDOWN RELAY.............................300
POWERTRAIN CONTROL MODULE C1 - GRAY/BLACK 40 WAY...............301
POWERTRAIN CONTROL MODULE C2 - GRAY/GRAY 40 WAY................302
10.0 SCHEMATIC DIAGRAMS................................................303
10.12001 RG 2.4L....................................................303
10.22001 RG 3.3L/3.8L................................................304
11.0 CHARTS AND GRAPHS................................................305
11.1SPECIFICATION..................................................305
v

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 information 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 DIAGNOSTIC
INFORMATION BEFORE TRYING TO DIAG-
NOSE A VEHICLE CODE. It is recommended that
you review the entire diagnostic information to
become familiar with all new and changed diagnos-
tic procedures.
If you have any comments or recommendations
after reviewing the diagnostic information, 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 2001 Town and Country; Caravan/Grand
Caravan; and Voyager/Grand Voyager vehicles
equipped with the 2.4L and the 3.3L/3.8L engines.
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
²Idle Air Control 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 OBD diagnostics incorpo-
rated with the Powertrain Control Module (PCM)
are intended to assist the field technician in repair-
ing vehicle problems by the quickest means.
3.2 FUNCTIONAL 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
enigne speed, manifold absolute pressure, and air
temperature change.
Different fuel calculation strategies are used de-
pending 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.
1
GENERAL INFORMATION

Once the auto shutdown and fuel pump relays
have been energized, the PCM determines the fuel
injector pulse width based on the following:
± engine coolant temperature
± manifold absolute pressure
± intake air temperature
± engine revolutions
± throttle position
The PCM determines the spark advance based on
the following:
± engine coolant temperature
± crankshaft position
± intake air temperature
± manifold absolute pressure
± throttle position
Engine Warm-Up Modeþ This is an open loop
mode. The PCM adjusts injector pulse width and
controls injector synchronization by controlling the
fuel injectors' ground paths. The PCM adjusts igni-
tion timing and engine idle speed. The PCM adjusts
the idle speed by controlling the idle air control
motor.
Cruise or Idle Modeþ When the engine is at
normal operating temperature, this is a closed loop
mode.
Acceleration Modeþ This is a closed loop mode.
The PCM recognizes an increase in throttle position
and a decrease in Manifold Vacuum as engine load
increases. In response, the PCM increases the in-
jector pulse width to meet the increased load. The
A/C compressor may be de-energized for a short
period of time.
Decelerationþ This is a closed loop mode. The
PCM recognizes a decrease in throttle position and
an increase in Manifold Vacuum as engine load
decreases. In response, the PCM decreases the
injector pulse width to meet the decreased load.
Full injector shut off may be obtained during high
speed deceleration.
Wide Open Throttle Modeþ This is an open
loop mode. The throttle position sensor notifies the
PCM of a wide open throttle condition. Once a wide
open throttle is sensed, the PCM de-energizes the
A/C compressor clutch relay for 20 seconds.
3.2.5 NON-MONITORED CIRCUITS
The PCM does not monitor the following circuits,
systems, and conditions even though they could
have malfunctions that result in driveability prob-
lems. A diagnostic code may not be displayed for the
following conditions. However, problems with these
systems may cause a diagnostic code to be displayed
for other systems. For example, a fuel pressure
problem will not register a diagnostic code directly,
but could cause a rich or lean condition. This couldcause an oxygen sensor, fuel system, or misfire
monitor trouble code to be stored in the PCM.
Engine Timingþ The PCM cannot detect an
incorrectly indexed timing chain, camshaft
sprocket, or crankshaft sprocket. The PCM also
cannot detect an incorrectly indexed distributor.(*)
Fuel Pressureþ Fuel pressure is controlled by
the fuel pressure regulator. The PCM cannot detect
a clogged fuel pump inlet filter, clogged in-line filter,
or a pinched fuel supply.(*)
Fuel Injectorsþ The PCM cannot detect if a fuel
injector is clogged, the pintle is sticking, or the
wrong injectors are installed.(*)
Fuel Requirementsþ Poor quality gasoline can
cause problems such as hard starting, stalling, and
stumble. Use of methanol-gasoline blends may re-
sult in starting and driveability problems. See indi-
vidual symptoms and their definitions in Section
6.0 (Glossary of Terms).
PCM Groundsþ The PCM cannot detect a poor
system ground. However, a diagnostic trouble code
may be stored in the PCM as a result of this
condition.
Throttle Body Air Flowþ The PCM cannot
detect a clogged or restricted air cleaner inlet or
filter element.(*)
Exhaust Systemþ The PCM cannot detect a
plugged, restricted, or leaking exhaust system.(*)
Cylinder Compressionþ The PCM cannot de-
tect uneven, low, or high engine cylinder compres-
sion.(*)
Excessive Oil Consumptionþ Although the
PCM monitors the exhaust stream oxygen content
through the oxygen sensor when the system is in a
closed loop, it cannot determine excessive oil con-
sumption.
NOTE: ANY OF THESE CONDITIONS
COULD RESULT IN A RICH OR LEAN
CONDITION CAUSING AN OXYGEN SENSOR
TROUBLE CODE TO BE STORED IN THE
PCM, OR THE VEHICLE MAY EXHIBIT ONE
OR MORE OF THE DRIVEABILITY
SYMPTOMS LISTED IN THE TABLE OF
CONTENTS.
3.2.6 SKIS OVERVIEW
The Sentry Key Immobilizer System (SKIS) is
designed to prevent unauthorized vehicle opera-
tion. The system consists of a Sentry Key Immobi-
lizer Module (SKIM), ignition key(s) equipped with
a transponder chip and PCM. When the ignition
switch is turned on, the SKIM interrogates the
ignition key. If the ignition key is Valid or Invalid,
the SKIM sends a PCI Bus message to the PCM
indicating ignition key status. Upon receiving this
5
GENERAL INFORMATION

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 DTC could be set, making diagnosis of the
original problem more difficult.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box) scan tool
Evaporative System Diagnostic Kit #6917
fuel filler adapter #8382
fuel pressure adapter (C-6631) or #6539
fuel pressure kit (C-4799-B) or #5069
fuel release hose (C-4799-1)
Min Air flow fitting #6714
jumper wires
ohmmeter
oscilloscope
vacuum gauge
voltmeter
12 volt test light minimum 25 ohms resistance
with probe #6801
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
ABSanti-lock brake system
backfire,
popbackfuel ignites in either the intake or
the exhaust system
CKPcrank position sensor
CMPcamshaft position sensorcuts out,
missesa steady pulsation or the inability of
the engine to maintain a consistent
rpm
DLCdata link connector (previously
called engine diagnostic connector)
detona-
tion,
spark
knocka mild to severe ping, especially un-
der loaded engine conditions
ECTengine coolant temperature sensor
EGRexhaust gas recirculation valve
genera-
torpreviously called alternator
hard
startThe engine takes longer than usual
to start, even though it is able to
crank normally.
hesita-
tion, sag,
stumbleThere is a momentary lack of re-
sponse when the throttle is opened.
This can occur at all vehicle speeds.
If it is severe enough, the engine
may stall.
IATintake air temperature sensor
IACidle air control motor
JTECCombined engine and transmission
control module
lack of
power,
sluggishThe engine has less than expected
power, with little or no increase in
vehicle speed when the throttle is
opened.
LDPleak detection pump
MAPmanifold absolute pressure sensor
MILmalfunction indicator lamp
MTVmanifold tuning valve
O2Soxygen sensor
PCIprogrammable communication inter-
face
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 ad configuration
12
GENERAL INFORMATION

POWERTRAIN VERIFICATION TEST VER - 2 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
4. With the DRBIIIt, clear DTCs and Reset Memory all engine values.
5. Run the engine for one warm-up cycle to verify proper operation.
6. Road test the vehicle. Use all accessories that may be related to this repair.
7. With the DRBIIIt, confirm that no DTC's or Secondary Indicators are present and that all
components are functioning properly.
8. If this test is being performed after a No Trouble Code test, verify the symptom is no longer
present.
9. If the symptom is still present, or any other symptom or DTC is present refer to the
appropriate category and perform the corresponding symptom.
10. Refer to any Technical Service Bulletins that may apply.
11. If there are no DTCs present and all components are functional properly, the repair is
complete.
Are any DTCs present?All
Ye s®Repair is not complete, refer to appropriate symptom.
No®Repair is complete.
POWERTRAIN VERIFICATION TEST VER - 3 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
4. With the DRBIIIt, clear DTCs.
5. Perform generator output test. Refer to the appropriate service information as necessary.
6. Start the engine and set engine speed to 2000 RPM for at least thirty seconds.
7. Cycle the ignition key off and on.
8. With the DRBIIIt, read the DTCs. If the DTC returns, or any other symptom or DTC is
present, refer to the appropriate category and perform the corresponding symptom.
9. If there are no DTCs present and all components are functioning properly, the repair is
complete.
Are any DTCs present?All
Ye s®Repair is not complete, refer to appropriate symptom.
No®Repair is complete.
277
VERIFICATION TESTS
VERIFICATION TESTS ÐContinued

POWERTRAIN VERIFICATION TEST VER - 4 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all engine components are properly installed and
connected.
4. Connect the DRB to the data link connector and erase all codes.
5. Turn the speed control ON (if equipped, cruise light will be on).
6. Depress and release the SET Switch. If the speed control did not engage, the repair is not
complete. Check for TSBs that pertain to speed control problem and then, if necessary, return
to Symptom List.
7. Depress and hold the RESUME/ACCEL Switch. If the vehicle speed did not increase by at
least 2 mph, the repair is not complete. Check for TSBs that pertain to speed control problem
and then, if necessary, return to Symptom List.
8. Press and hold the COAST switch. The vehicle speed should decrease. If it did not decrease,
the repair is not complete. Check for TSBs that pertain to speed control problem and then, if
necessary, return to Symptom List.
9. Using caution, depress and release the brake pedal. If the speed control did not disengage,
the repair is not complete. Check for TSBs that pertain to speed control problem and then, if
necessary, return to Symptom List.
10. Bring the vehicle speed back up to 35 MPH.
11. Depress the RESUME/ACCEL switch. If the speed control did not resume the previously set
speed, the repair is not complete. Check for TSBs that pertain to speed control problem and
then, if necessary, return to Symptom List.
12. Hold down the SET switch. If the vehicle did not decelerate, the repair is not complete.
Check for TSBs that pertain to speed control problem and then, if necessary, return to
Symptom List.
13. Ensure vehicle speed is greater than 35 mph and release the SET Switch. If vehicle did not
adjust and set a new vehicle speed, the repair is not complete. Check for TSBs that pertain to
speed control problem and then, if necessary, return to Symptom List.
14. Depress and release the CANCEL switch. If the speed control did not disengage, the repair
is not complete. Check for TSBs that pertain to speed control problem and then, if necessary,
return to Symptom List.
15. Bring the vehicle speed back up above 35 mph and engage speed control.
16. Depress the OFF switch to turn OFF, (Cruise light will be off). If the speed control did not
disengage, the repair is not complete. Check for TSBs that pertain to speed control problem and
then, if necessary, return to Symptom List.
17. If the vehicle successfully passed all of the previous tests, the speed control system is now
functioning as designed. The repair is now complete.
Did the Speed Control pass the above test?All
Ye s®Repair is complete.
No®Repair is not complete, refer to appropriate symptom.
278
VERIFICATION TESTS
VERIFICATION TESTS ÐContinued

POWERTRAIN VERIFICATION TEST VER - 5 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all engine components are properly installed and
connected. Reassemble and reconnect components as necessary.
4. Connect the DRBIIItto the data link connector.
5. Ensure the fuel tank has at least a quarter tank of fuel. Turn off all accessories.
6. If a Comprehensive Component DTC was repaired, perform steps5-8.IfaMajor OBDII
Monitor DTC was repaired skip those steps and continue verification.
7. After the ignition has been off for at least 10 seconds, restart the vehicle and run 2 minutes.
8. If the Good Trip counter changed to one or more and there are no new DTC's, the repair was
successful and is now complete. Erase DTC's and disconnect the DRBIIIt.
9. If the repaired DTC has reset, the repair is not complete. Check for any related TSB's or flash
updates and return to the Symptom list.
10. If another DTC has set, return to the Symptom List and follow the path specified for that
DTC.
11. With the DRBIIIt, monitor the appropriate pre-test enabling conditions until all conditions
have been met. Once the conditions have been met, switch screen to the appropriate OBDII
monitor, (Audible beeps when the monitor is running).
12. If the monitor ran, and the Good Trip counter changed to one or more, the repair was
successful and is now complete. Erase DTC's and disconnect the DRBIIIt.
13. If the repaired OBDII trouble code has reset or was seen in the monitor while on the road
test, the repair is not complete. Check for any related technical service bulletins or flash
updates and return to Symptom List.
14. If another DTC has set, return to the Symptom List and follow the path specified for that
DTC.
Are any DTCs present?All
Ye s®Repair is not complete, refer to appropriate symptom.
No®Repair is complete.
279
VERIFICATION TESTS
VERIFICATION TESTS ÐContinued

POWERTRAIN VERIFICATION TEST VER - 6 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all engine components are properly installed and
connected. Reassemble and reconnect components as necessary.
4. The LDP Monitor Test Mode has been added to the DRBIII to verify repairs to the LDP
System. A DRB software program was written which causes the PCM to run the LDP Monitor
as part of this test. Test failures will be indicated through a stored DTC.
5. LDP Monitor Test Mode is a useful way to run a total system performance test. Use this test
to verify any type of LDP system repair.
6. Software program makes temporary changes to operating mode of PCM. For this reason, it
is critical that test not be interrupted. PCM's left in this mode as result of interrupted test will
illuminate the MIL for 8-10 mi of driving with no DTC's stored.
7. Erasing DTC's will not change this condition.
8. If a vehicle is found to be stuck in the mode described above, the LDP Dealer Test should be
re-run in its entirety so that the software program in the DRBIII can restore the PCM
operating mode.
9. Note similarity to LDP Monitor screen found under OBDII Monitors. Failure modes are
fewer in this System Test than OBDII LDP Monitor. System Test only stores Small Leak DTC
to indicate problem with system. No other type of failure mode indication given.
10. System Test failure may have been, for example, due to a large leak, but the PCM will set
the Small Leak DTC to indicate failures that occurred as part of the system test.
11. Connect the DRB to the data link connector. Engine running, turn off all accessories.
12. Note: While test is being performed, PCM must see RPM, minimum MAP, No Vehicle speed
and minimum Throttle Position sensor (At idle, in park.) With DRBIII in System Tests, perform
the LDP Monitor Test and follow the instructions on the screen.
13. If the LDP Monitor Test failed and a Small Leak DTC has set, the repair is not complete.
Check for any related Technical Service Bulletins and return to Symptom List.
14. If any other trouble code has set, return to Symptom List and follow the path specified for
that trouble code. If the LDP Monitor Test passed, the repair was successful and testing is now
complete.
Are any DTCs present?All
Ye s®Repair is complete.
No®Repair is not complete, refer to appropriate symptom.
280
VERIFICATION TESTS
VERIFICATION TESTS ÐContinued