lock CHRYSLER VOYAGER 2001 Service Manual

A pressure build up within the evaporative system
may cause pressure on the lower side of the LDP dia-
phragm. This will cause the LDP diaphragm to
remain in its9up9position (stuck in the up position).
This condition can occur even when the solenoid
valve is deenergized. This condition can be caused by
previous cycling (pumping) of the LDP by the techni-
cian (dealer test). Another way that this condition is
created is immediately following the running of the
vehicle evaporative system monitor. In this case, the
PCM has not yet opened the proportional purge sole-
noid in order to vent the pressure that has been built
up in the evaporative system to the engine combus-
tion system. The technician will need to vent the
evaporative system pressure via the vehicle fuel filler
cap and its fuel filler secondary seal (if so equipped
in the fuel filler neck). This will allow the technician
to cycle the LDP and to watch switch state changes.
After passing the leak detection phase of the test,
system pressure is maintained until the purge sys-
tem is activated, in effect creating a leak. If the dia-
phragm falls (as is expected), causing the reed switch
to change state, then the diagnostic test is completed.
When one of the evaporative system leak monitors
begins its various tests, a test is performed to deter-
mine that no part of the evaporative system is
blocked. In this test, the LDP is cycled (pumped) a
calibrated (few) number of times. Pressure should not
build up in the evaporative system. If pressure is
present, then LDP diaphragm is forced to stay in its
9up9position. The reed switch now stays open and
the PCM senses this open (incorrect) state. The evap-
orative system monitor will fail the test because of a
detected obstruction within the system.
Possible causes:
²Open or shorted LDP switch sense circuit
²Leak Detection Pump switch failure
²Open fused ignition switch output
²Restricted, disconnected, or blocked manifold
vacuum source
²Obstruction of hoses or lines
²PCM failure
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Remove 3 hoses (Fig. 4).
(4) Remove the electrical connector (Fig. 5) .
(5) Remove the 3 screws and remove LDP pump.
INSTALLATION
(1) Install LDP.
(2) Install the 3 screws and tighten (Fig. 5).
(3) Install the electrical connector.
(4) Install the 3 hoses (Fig. 4).(5) Lower vehicle.
(6) Connect the negative battery cable.
Fig. 4 LDP LOCATION
Fig. 5 LDP REMOVAL/INSTALLATION
25 - 14 EVAPORATIVE EMISSIONSRS
LEAK DETECTION PUMP (Continued)

PCV VALVE
DESCRIPTION
The PCV valve contains a spring loaded plunger.
The plunger meters the amount of crankcase vapors
routed into the combustion chamber based on intake
manifold vacuum.
OPERATION
When the engine is not operating or during an
engine backfire, the spring forces the plunger back
against the seat. This prevents vapors from flowing
through the valve (Fig. 8).
When the engine is at idle or cruising, high mani-
fold vacuum is present. At these times manifold vac-
uum is able to completely compress the spring and
pull the plunger to the top of the valve (Fig. 9). In
this position there is minimal vapor flow through the
valve.During periods of moderate intake manifold vac-
uum the plunger is only pulled part way back from
the inlet. This results in maximum vapor flow
through the valve (Fig. 10).
DIAGNOSIS AND TESTING - PCV SYSTEM
INSPECTION
WARNING: APPLY PARKING BRAKE AND/OR
BLOCK WHEELS BEFORE PERFORMING ANY TEST
OR ADJUSTMENT WITH THE ENGINE OPERATING.
(1) With engine idling, remove the hose from the
PCV valve. If the valve is not plugged, a hissing
noise will be heard as air passes through the valve. A
strong vacuum should also be felt when a finger is
placed over the valve inlet.
(2) Install hose on PCV valve. Remove the
make-up air hose from the air plenum at the rear of
the engine. Hold a piece of stiff paper (parts tag)
loosely over the end of the make-up air hose.
(3)
After allowing approximately one minute for
crankcase pressure to reduce, the paper should draw up
against the hose with noticeable force. If the engine
does not draw the paper against the grommet after
installing a new valve, replace the PCV valve hose.
(4)Turn the engine off. Remove the PCV valve from
intake manifold. The valve should rattle when shaken.
(5) Replace the PCV valve and retest the system if
it does not operate as described in the preceding
tests.Do not attempt to clean the old PCV valve.
If the valve rattles, apply a light coating of Loctitet
Pipe Sealant With Teflon to the threads. Thread the
PCV valve into the manifold plenum and tighten to 7
N´m (60 in. lbs.) torque.
Fig. 7 PCV VALVE 2.4L
1 - PCV Valve
Fig. 8 Engine Off or Engine Backfire No Vapor Flow
Fig. 9 High Intake Manifold Vacuum Minimal Vapor
Flow
Fig. 10 Moderate Intake Manifold Vacuum Maximum
Vapor Flow
RSEVAPORATIVE EMISSIONS25-17

EXHAUST GAS RECIRCULATION
TABLE OF CONTENTS
page page
EXHAUST GAS RECIRCULATION
DESCRIPTION............................3
OPERATION.............................3
VA LV E
DESCRIPTION............................3
OPERATION.............................4REMOVAL...............................4
INSTALLATION............................4
VALVE COOLER
DESCRIPTION............................4
REMOVAL...............................4
INSTALLATION............................5
EXHAUST GAS
RECIRCULATION
DESCRIPTION
The EGR system reduces oxides of nitrogen (NOx)
in the engine exhaust. This is accomplished by allow-
ing a predetermined amount of hot exhaust gas to
recirculate and dilute the incoming fuel/air mixture.
A malfunctioning EGR system can cause engine
stumble, sags, or hesitation, rough idle, engine stall-
ing and poor driveability.
OPERATION
The system consists of:
²An EGR valve assembly. The valve is located on
the rear of the engine above the exhaust manfiold.
²An EGR solenoid.The EGR solenoid controls the
ªon timeº of the EGR valve.
²The ECM operates the EGR solenoid. The ECM
is located inside the vehicle under the instrument
panel.
²An EGR tube connects a passage in the EGR
valve to the rear of the exhaust manifold.
²The vacuum pump supplies vacuum for the EGR
solenoid and the EGR valve. This pump also supplies
vacuum for operation of the power brake boosterb
and the heating and air conditioning system. The
pump is located internally in the front of the engine
block and is driven by the crankshaft gear.
²Vacuum lines and hoses connect the various
components.
When the ECM supplies a variable ground signal
to the EGR solenoid, EGR system operation starts to
occur. The ECM will monitor and determine when tosupply and remove this variable ground signal. This
will depend on inputs from the engine coolant tem-
perature, throttle position and engine speed sensors.
When the variable ground signal is supplied to the
EGR solenoid, vacuum from the vacuum pump will
be allowed to pass through the EGR solenoid and on
to the EGR valve with a connecting hose.
Exhaust gas recirculation will begin in this order
when:
²The ECM determines that EGR system opera-
tion is necessary.
²The engine is running to operate the vacuum
pump.
²A variable ground signal is supplied to the EGR
solenoid.
²Variable vacuum passes through the EGR sole-
noid to the EGR valve.
²The inlet seat (poppet valve) at the bottom of
the EGR valve opens to dilute and recirculate
exhaust gas back into the intake manifold.
The EGR system will be shut down by the ECM
after 60 seconds of continuous engine idling to
improve idle quality.
VA LV E
DESCRIPTION
The EGR system consists of (Fig. 1):
²EGR valve
²EGR tube
²Vacuum hoses
²EGR cooler
²EGR solenoid
RGEXHAUST GAS RECIRCULATION25a-3

TABLE OF CONTENTS - Continued
P0325-KNOCK SENSOR #1 CIRCUIT......................................113
P0340-NO CAM SIGNAL AT PCM.........................................116
P0351-IGNITION COIL #1 PRIMARY CIRCUIT..............................121
P0352-IGNITION COIL #2 PRIMARY CIRCUIT..............................121
P0353-IGNITION COIL #3 PRIMARY CIRCUIT..............................121
P0401 - EGR SYSTEM FAILURE.........................................124
P0403 - EGR SOLENOID CIRCUIT........................................128
P0420-1/1 CATALYTIC CONVERTER EFFICIENCY...........................131
P0441-EVAP PURGE FLOW MONITOR....................................133
P0442-EVAP LEAK MONITOR MEDIUM (.040) LEAK DETECTED...............136
P0455-EVAP LEAK MONITOR LARGE LEAK DETECTED.....................136
P0456 - EVAP LEAK MONITOR SMALL LEAK DETECTED....................136
P0443-EVAP PURGE SOLENOID CIRCUIT.................................139
P0460-FUEL LEVEL UNIT NO CHANGE OVER MILES........................142
P0462-FUEL LEVEL SENDING UNIT VOLTS TOO LOW.......................145
P0463-FUEL LEVEL SENDING UNIT VOLTS TOO HIGH......................145
P0500-NO VEHICLE SPEED SIGNAL (3SP AUTO AND MANUAL
TRANSMISSIONS).....................................................147
P0500-NO VEHICLE SPEED SIGNAL (4SP AUTO TRANS)....................150
P0505-IDLE AIR CONTROL MOTOR CIRCUITS.............................153
P0508 - IAC MOTOR SENSE CIRCUIT LOW................................156
P0509 - IAC MOTOR SENSE CIRCUIT HIGH...............................159
P0700-EATX CONTROLLER DTC PRESENT................................161
P0703-BRAKE SWITCH SENSE CIRCUIT..................................162
P0740-TORQ CONV CLU, NO RPM DROP AT LOCKUP (3SP AUTO TRANS).....165
P0743-TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CIRCUITS
(3SP AUTO TRANS)....................................................168
P0833-CLUTCH RELEASED SWITCH CIRCUIT.............................171
P1192-INLET AIR TEMP SENSOR VOLTAGE LOW...........................174
P1193-INLET AIR TEMP SENSOR VOLTAGE HIGH..........................176
P1195-1/1 O2 SENSOR SLOW DURING CATALYST MONITOR................178
P1281-ENGINE IS COLD TOO LONG......................................180
P1282-FUEL PUMP RELAY CONTROL CIRCUIT.............................181
P1294-TARGET IDLE NOT REACHED (2.4L)................................184
P1294-TARGET IDLE NOT REACHED (3.3L/3.8L)............................187
P1297-NO CHANGE IN MAP FROM START TO RUN.........................189
P1299-VACUUM LEAK FOUND (IAC FULLY SEATED)........................193
P1388-AUTO SHUTDOWN RELAY CONTROL CIRCUIT.......................195
P1389-NO ASD RELAY OUTPUT VOLTAGE AT PCM.........................198
P1391-INTERMITTENT LOSS OF CMP OR CKP.............................201
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT.........................205
P1486-EVAP LEAK MONITOR PINCHED HOSE FOUND......................207
P1491-RAD FAN CONTROL RELAY CIRCUIT...............................210
P1494-LEAK DETECT PUMP SW OR MECHANICAL FAULT...................214
P1495-LEAK DETECTION PUMP SOLENOID CIRCUIT.......................216
P1496-5 VOLT SUPPLY, OUTPUT TOO LOW...............................218
P1602-PCM NOT PROGRAMMED........................................221
P1899-P/N SWITCH STUCK IN PARK OR IN GEAR (3SP AUTO TRANS)........222
P1899-P/N SWITCH STUCK IN PARK OR IN GEAR (4SP AUTO TRNAS)........224
*CHECKING ECT SENSOR..............................................226
*CHECKING FUEL DELIVERY............................................227
*CHECKING IAC MOTOR (2.4L)..........................................231
*CHECKING IAT SENSOR...............................................232
iii

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

3. Select PCM REPLACED.
4. Enter secured access mode by entering the vehi-
cle four-digit PIN.
NOTE: IF THREE ATTEMPTS ARE MADE TO
ENTER THE SECURE ACCESS MODE USING
AN INCORRECT PIN, SECURED ACCESS
MODE WILL BE LOCKED OUT FOR ONE
HOUR. TO EXIT THIS LOCKOUT MODE,
TURN THE IGNITION TO THE RUN POSITION
FOR ONE HOUR THEN ENTER THE
CORRECT PIN. (ENSURE ALL ACCESSORIES
ARE TURNED OFF. ALSO MONITOR THE
BATTERY STATE AND CONNECT A BATTERY
CHARGER IF NECESSARY).
5. Press ENTER to transfer the secret key (the
SKIM will send the secret key to the PCM).
3.2.10 PROGRAMMING THE SENTRY KEY
IMMOBILIZER MODULE
NOTE: IF THE PCM AND THE SKIM ARE
REPLACED AT THE SAME TIME, PROGRAM
THE VIN INTO THE PCM FIRST. ALL VEHICLE
KEYS WILL THEN NEED TO BE REPLACED
AND PROGRAMMED TO THE NEW SKIM.
1. Turn the ignition on (transmission in park/
neutral).
2. Use the DRB and select THEFT ALARM, SKIM
then MISCELLANEOUS.
3. Select SKIM MODULE REPLACEMENT (GAS-
OLINE).
4. Program the vehicle four-digit PIN into the
SKIM.
5. Select COUNTRY CODE and enter the correct
country.
NOTE: BE SURE TO ENTER THE CORRECT
COUNTRY CODE. IF THE INCORRECT
COUNTRY CODE IS PROGRAMMED INTO
SKIM, THE SKIM MUST BE REPLACED.
6. Select UPDATE VIN (the SKIM will learn the
VIN from the PCM).
7. Press ENTER to transfer the VIN (the PCM will
send the VIN to the SKIM).
8. The DRB will ask if you want to transfer the
secret key. Select ENTER to transfer secret key
from the PCM. This will ensure the current
vehicle ignition keys will still operate the SKIS
system.
3.2.11 PROGRAMMING THE IGNITION
KEYS TO THE SENTRY KEY
IMMOBILIZER MODULE
1. Turn the ignition on (transmission in park/
neutral).
2. Use the DRB and select THEFT ALARM, SKIM,
then MISCELLANEOUS.
3. Select PROGRAM IGNITION KEYS.
4. Enter secured access mode by entering the vehi-
cle four-digit PIN.
NOTE: A MAXIMUM OF EIGHT KEYS CAN BE
LEARNED TO EACH SKIM AT ONE TIME.
ONCE A KEY IS LEARNED TO A SKIM IT (THE
KEY) CANNOT BE TRANSFERRED TO
ANOTHER VEHICLE.
If ignition key programming is unsuccessful, the
DRB will display one of the following messages:
Programming Not Attempted- The DRB at-
tempts to read the programmed key status and
there are no keys programmed in the SKIM mem-
ory.
Programming Key Failed -(Possible Used Key
From Wrong Vehicle) - SKIM is unable to program
key due to one of the following:
± faulty ignition key transponder
± ignition key is programmed to another vehicle.
8 Keys Already Learned, Programming Not
Done- SKIM transponder ID memory is full.
1. Obtain ignition keys to be programmed from
customer (8 keys maximum)
2. Using the DRB, erase all ignition keys by select-
ing MISCELLANEOUS and ERASE ALL CUR-
RENT IGN. KEYS
3. Program all ignition keys.
Learned Key In Ignition- Ignition key transpon-
der ID is currently programmed in SKIM memory.
3.3 DIAGNOSTIC TROUBLE CODES
Each diagnostic trouble code is diagnosed by
following a specific testing procedure. The diagnos-
tic test procedures contain step-by-step instructions
for determining the cause of trouble codes as well as
no trouble code problems. It is not necessary to
perform all of the tests in this book to diagnose an
individual code.
Always begin by reading the diagnostic trouble
codes using the DRBIIIt.
3.3.1 HARD CODE
A diagnostic trouble code that comes back within
one cycle of the ignition key is a hard code. This
means that the defect is there every time the
7
GENERAL INFORMATION

SYMPTOM DIAGNOSTIC TEST
POOR FUEL ECONOMY CHECKING PCM POWER AND GND CKT
CHECKING THE FUEL PRESSURE
CHECKING ECT SENSOR
CHECKING THROTTLE POSITION SENSOR
CHECKING MAP SENSOR
CHECKING IDLE AIR CONTROL MOTOR OPERATION
CHECKING IAT SENSOR
3.4 USING THE DRBIIIT
Refer to the DRBIIItuser 's guide for instructions
and assistance with reading DTC's, erasing DTC's,
and other DRBIIItfunctions.
3.5 DRBIIITERROR 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
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 DRBIIITDOES 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 the vehicle or other devices, and the
vehicle battery is fully charged, and inoperative
DRBIIItmay be the result of faulty cable or vehicle
wiring.
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
10
GENERAL INFORMATION

important 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
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 DRB if 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
FUNCTION INPUT LIMIT
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 DRBIIIt
away from spark plug or coil wires to avoid mea-
suring 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 DRBIIITSCREEN WHILE IN
MOTION. DO NOT HANG THE DRBIIITFROM
THE REAR VIEW MIRROR OR OPERATE IT
YOURSELF. HAVE AN ASSISTANT
AVAILABLE TO OPERATE THE DRBIIIT.
4.3.2 VEHICLE DAMAGE CAUTIONS
Before disconnecting any control module, make
sure the ignition is off. Failure to do so could
damage the module.
11
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

Symptom:
*NO RESPONSE FROM PCM (PCI BUS)
POSSIBLE CAUSES
PCM PCI NO RESPONSE
PCI BUS CIRCUIT OPEN
POWERTRAIN CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
NOTE: As soon as one or more module communicates with the DRB, answer
the question.
With the DRB, enter Body then Body Computer.
With the DRB, enter Anti-Lock Brakes.
With the DRB, enter Body then Electro/Mechanical Cluster (MIC).
With the DRB, enter Passive Restraints then Airbag.
Were you able to establish communications with any of the modules?All
Ye s®Go To 2
No®Refer to symptom PCI Bus Communication Failure in the Com-
munications category.
Perform POWERTRAIN VERIFICATION TEST VER-1.
2 With the DRB read PCM Diagnostic Trouble Codes. This is to ensure power and
grounds to the PCM are operational.
NOTE: If the DRB will not read PCM DTC's, follow the NO RESPONSE TO
PCM (SCI only) symptom path, if vehicle will start. For NO START Condi-
tions follow symptom NO RESPONSE in Starting category.
Turn the ignition off.
Disconnect the PCM C2 harness connector.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
Select DRB Standalone.
Select lab scope.
Select Live.
Select 12 volt square wave.
Press F2 for Scope.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the PCM ground. Connect the Red lead to the PCI Bus
circuit in the PCM connector.
Turn the ignition on.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Replace the Powertrain Control Module in accordance with the
Service Information.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Repair the PCI Bus circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER-1.
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COMMUNICATION