fuses DODGE NEON 2000 Service User Guide
[x] Cancel search | Manufacturer: DODGE, Model Year: 2000, Model line: NEON, Model: DODGE NEON 2000Pages: 1285, PDF Size: 29.42 MB
Page 362 of 1285

REMOVAL
(1) Disconnect and isolate the battery negative
cable (Fig. 4).
(2) Disconnect each of the engine compartment
wire harness connectors. Refer to8W-90 - Connec-
tor Locationsin Group 8W - Wiring Diagrams for
more information on the locations of the affected con-
nectors.
(3) Remove the fasteners that secure each of the
engine compartment wire harness ground eyelets to
the vehicle body and chassis components. Refer to
8W-90 - Connector Locationsin Group 8W - Wir-
ing Diagrams for more information on the ground
eyelet locations.
(4) Disengage each of the retainers that secure the
engine compartment wire harness to the vehicle body
and chassis components. Refer to8W-90 - Connec-tor Locationsin Group 8W - Wiring Diagrams for
more information on the retainer locations.
(5) Remove the one screw and disengage the PDC
housing from the left inner fender well.
(6) Remove the PDC and the engine compartment
wire harness from the engine compartment as a unit.
INSTALLATION
NOTE: If the power distribution center (PDC) is
being replaced with a new unit, be certain to trans-
fer each of the fuses and relays from the old power
distribution center to the proper cavities of the new
power distribution center. Refer to Power Distribu-
tion in Group 8W - Wiring Diagrams for the proper
power distribution center cavity assignments.
(1) Position the PDC in the engine compartment.
(2) Align the PDC mounting pin with the inner
fender well hole.
(3) Place PDC down in engine compartment and
install retaining screw.
(4) Route the engine compartment wire harness
from the PDC through the engine compartment,
engaging each of the harness retainers to the mount-
ing provisions in the vehicle body and chassis compo-
nents. Refer to8W-90 - Connector Locationsin
Group 8W - Wiring Diagrams for more information
on the harness routing and retainer locations.
(5) Install and tighten the fasteners that secure
each of the engine compartment wire harness ground
eyelets to the vehicle body and chassis components.
Refer to8W-90 - Connector Locationsin Group
8W - Wiring Diagrams for more information on the
ground eyelet locations.
(6) Reconnect each of the engine compartment
wire harness connectors. Refer to8W-90 - Connec-
tor Locationsin Group 8W - Wiring Diagrams for
more information on the locations of the affected con-
nectors.
(7) Torque nut retaining positive battery cable at
PDC to 96 - 141 Nzm (85 - 130 in. lbs.).
(8) Reconnect the battery negative cable.
Fig. 4 Battery Negative Cable Remove/Install
1 ± NEGATIVE CABLE
2 ± NEGATIVE BATTERY POST
PLPOWER DISTRIBUTION SYSTEMS 8O - 3
REMOVAL AND INSTALLATION (Continued)
Page 365 of 1285

first turn) will cause all vehicle doors to unlock elec-
trically. When this feature is disabled, all vehicle
doors will be unlocked electrically upon the first turn
of a key cylinder to the UNLOCK position. The vehi-
cle is locked electrically by turning the key cylinder
to the LOCK position once, regardless of the state of
the double activation unlock feature.
POWER DOOR LOCKS
The Remote Keyless Entry (RKE) Module actuates
the power door lock relays when a door lock switch is
activated. If the door lock switch is pressed for longer
than eight consecutive seconds, the RKE module will
de-energize the door lock motors.
The system includes the rolling door locking fea-
ture. The vehicle is shipped with the system enabled.
When the system is disabled the door locks will work
by use of the door lock switches and the Remote Key-
less Entry system only. When the rolling door lock
system is enabled, the RKE module will automati-
cally lock all the vehicle doors when all of the follow-
ing conditions are met:
²All doors are closed
²The vehicle speed exceeds 15 +/- 1 mph.
²The throttle position sensor tip-in is greater
than 10 +/- 2 degrees.
The RKE module will automatically re-lock all
doors if the above conditions are met and if any of
the doors become ajar and then closed again.
The enabling/disabling of the rolling door lock fea-
ture is customer programmable, as well as program-
mable with the DRB IIItscan tool.
The power lock motors are also equipped with a
thermal protection system which prevents the motors
from burning out. The motors may chatter if they are
continuously activated.
CHILD PROTECTION LOCKS
The child protection locks are on the rear doors
only. The lock, when engaged, will disable the inside
door handle from opening the door. The lock is part
of the latch/lock assembly. The lock is engaged by
moving a lever that is located on the rearward inside
edge of the door.
DOOR LOCK INHIBIT
With the key in the ignition switch and the driver
door open, the Remote Keyless Entry (RKE) Modulewill ignore the command to lock the power door locks
via the interior driver door lock switch. Once the key
is removed, or the driver door is closed, the RKE
module will allow the power door locks to lock via the
interior door lock switches.
DIAGNOSIS AND TESTING
DOOR LOCK MOTOR
(1) Make certain battery is in normal condition
and fuses powering the RKE module aren't blown
before circuits are tested.
(2) To determine which motor is faulty, check each
individual door for electrical lock and unlock or dis-
connect the motor connectors one at a time, while
operating the door lock switch.
(3) In the event that none of the motors work, the
problem maybe caused by a shorted motor, a bad
switch or a bad relay internal to the RKE module.
Disconnecting a defective motor will allow the others
to work.
(4) To test an individual door lock motor, discon-
nect the electrical connector from the motor.
(5) To lock the door, connect a 12 volt power source
to one pin of the lock motor and a ground wire to the
other pin.
(6) To unlock the door, reverse the wire connec-
tions at the motor pin terminals.
(7) If these results are NOT obtained, replace the
motor.
DOOR LOCK SWITCH
(1) Remove the switch from its mounting location,
and disconnect from vehicle wiring harness. Refer to
Door Lock Switch Removal and Installation in this
section.
(2) Using an ohmmeter, refer to Door Lock Switch
Resistance Test table to determine if switch resis-
tance is correct in the Lock and Unlock switch posi-
tions. Refer to Group 8W-Wiring Diagrams for
harness connector pin-outs.
DOOR LOCK SWITCH RESISTANCE
SWITCH POSITION CONTINUITY BETWEEN RESISTANCE VALUE
LOCK 2 AND 3 1000V
UNLOCK 2 AND 3 249V
8P - 2 POWER LOCK SYSTEMSPL
DESCRIPTION AND OPERATION (Continued)
Page 375 of 1285

memory to determine whether a valid key is in the
ignition lock cylinder.
The Sentry Key transponder cannot be repaired
and, if faulty or damaged, it must be replaced.
SENTRY KEY IMMOBILIZER SYSTEM
INDICATOR LAMP
The Sentry Key Immobilizer System (SKIS) uses
the Vehicle Theft Security System (VTSS) indicator
LED to give an indication when the SKIS is faulty or
when the vehicle has been immobilized due to the
use of an invalid ignition key. The LED is controlled
by the instrument cluster circuitry based upon mes-
sages received from the Sentry Key Immobilizer
Module (SKIM) through the Body Control Module
(BCM) on the Programmable Communication Inter-
face (PCI) bus.
The SKIM sends messages to the instrument clus-
ter, via the BCM, to turn the LED on for about three
seconds when the ignition switch is turned to the ON
position as a bulb test. After completion of the bulb
test, the SKIM sends PCI bus messages to keep the
LED off for a duration of about one second. Then the
SKIM sends messages to the instrument cluster cir-
cuitry to turn the LED on or off based upon the
results of the SKIS self-tests. If the VTSS indicator
LED comes on and stays on after the bulb test, it
indicates that the SKIM has detected a system mal-
function and/or that the SKIS has become inopera-
tive. If the SKIM detects an invalid key when the
ignition switch is turned to the ON position, it sends
messages to the instrument cluster to flash the VTSS
indicator LED.
The SKIM can also send messages to the instru-
ment cluster to flash the LED and to generate a sin-
gle audible chime tone. These functions serve as an
indication to the customer that the SKIS has been
placed in its ªCustomer Learnº programming mode.
See Sentry Key Immobilizer System Transponder
Programming in this group for more information on
the ªCustomer Learnº programming mode.
The VTSS indicator LED uses a replaceable Light
Emitting Diode (LED) on the instrument cluster elec-
tronic circuit board. Refer to Group 8E - Instrument
Panel Systems for Cluster Lamp Removal and Instal-
lation. If the VTSS indicator LED comes on and
stays on after the bulb test function, diagnosis of the
SKIS should be performed with a DRB IIItscan tool
and the proper Body Diagnostic Procedures Manual.
TRIGGERING THE VTSS
After the VTSS is armed, any of the following will
trigger the system:
²Opening any door.
²Opening the hood.
²Removing the trunk lock cylinder.²Turning the ignition to the RUN/START position
with an invalid Sentry Key.
NOTE: The ignition switch can be turned to the
accessory position without triggering the alarm sys-
tem.
DIAGNOSIS AND TESTING
SENTRY KEY IMMOBILIZER SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
NOTE: The following tests may not prove conclu-
sive in the diagnosis of this system. The most reli-
able, efficient, and accurate means to diagnose the
Sentry Key Immobilizer System (SKIS) involves the
use of a DRB lllTscan tool and the proper Body
Diagnostic Procedures Manual.
The Sentry Key Immobilizer System (SKIS) and
the Programmable Communication Interface (PCI)
bus network should be diagnosed using a DRB lllt
scan tool. The DRB IIItwill allow confirmation that
the PCI bus is functional, that the Sentry Key Immo-
bilizer Module (SKIM) is placing the proper messages
on the PCI bus, and that the Powertrain Control
Module (PCM) and the instrument cluster are receiv-
ing the PCI bus messages. Refer to the proper Body
Diagnostic Procedures Manual. Refer to Group
8W-Wiring Diagrams for complete circuit descriptions
and diagrams.
(1) Check the fuses in the fuse block. If OK, go to
Step 2. If not OK, repair the shorted circuit or com-
ponent as required and replace the faulty fuse.
(2) Disconnect and isolate the battery negative
cable (Fig. 3). Unplug the wire harness connector at
the SKIM. Check for continuity between the ground
circuit cavity of the SKIM wire harness connector
and a good ground. There should be continuity. If
OK, go to Step 3. If not OK, repair the open circuit to
ground as required.
(3) Connect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
SKIM wire harness connector. If OK, go to Step 4. If
not OK, repair the open circuit to the fuse in the fuse
block as required.
8Q - 4 VEHICLE THEFT/SECURITY SYSTEMPL
DESCRIPTION AND OPERATION (Continued)
Page 402 of 1285

²Connectors are fully seated
²Spread terminals, or terminal push out
²Terminals in the wiring assembly are fully
seated into the connector/component and locked in
position
²Dirt or corrosion on the terminals. Any amount
of corrosion or dirt could cause an intermittent prob-
lem
²Damaged connector/component casing exposing
the item to dirt and moisture
²Wire insulation that has rubbed through causing
a short to ground
²Some or all of the wiring strands broken inside
of the insulation covering
²Wiring broken inside of the insulation.
TROUBLESHOOTING TESTS
Before beginning any tests on a vehicles electrical
system use the Wiring Diagrams and study the cir-
cuit. Also refer to the Troubleshooting Wiring Prob-
lems in this section.
TESTING FOR VOLTAGE POTENTIAL
(1) Connect the ground lead of a voltmeter to a
known good ground (Fig. 4).
(2) Connect the other lead of the voltmeter to the
selected test point. The vehicle ignition may need to
be turned ON to check voltage. Refer to the appropri-
ate test procedure.
TESTING FOR CONTINUITY
(1) Remove the fuse for the circuit being checked
or, disconnect the battery.(2) Connect one lead of the ohmmeter to one side
of the circuit being tested (Fig. 5).
(3) Connect the other lead to the other end of the
circuit being tested. Low or no resistance means good
continuity.
TESTING FOR A SHORT TO GROUND
(1) Remove the fuse and disconnect all items
involved with the fuse.
(2) Connect a test light or a voltmeter across the
terminals of the fuse.
(3) Starting at the fuse block, wiggle the wiring
harness about six to eight inches apart and watch
the voltmeter/test lamp.
(4) If the voltmeter registers voltage or the test
lamp glows, there is a short to ground in that gen-
eral area of the wiring harness.
TESTING FOR A SHORT TO GROUND ON FUSES
POWERING SEVERAL LOADS
(1) Refer to the wiring diagrams and disconnect or
isolate all items on the suspected fused circuits.
(2) Replace the blown fuse.
(3) Supply power to the fuse by turning ON the
ignition switch or re-connecting the battery.
(4) Start connecting the items in the fuse circuit
one at a time. When the fuse blows the circuit with
the short to ground has been isolated.
TESTING FOR A VOLTAGE DROP
(1) Connect the positive lead of the voltmeter to
the side of the circuit closest to the battery (Fig. 6).
Fig. 4 Testing for Voltage Potential
Fig. 5 Testing for Continuity
1 ± FUSE REMOVED FROM CIRCUIT
PL8W - 01 GENERAL INFORMATION 8W - 01 - 9
DIAGNOSIS AND TESTING (Continued)
Page 410 of 1285

8W-02 COMPONENT INDEX
Component Page
A/C Compressor Clutch Relay............8W-42
A/C Compressor Clutch.................8W-42
A/C Cycling Switch....................8W-42
A/C Heater Blower Motor...............8W-42
A/C Heater Control....................8W-42
A/C Pressure Switches..................8W-42
Airbag Control Module.................8W-43
Airbags.............................8W-43
Antenna.............................8W-47
Automatic Shut Down Relay.............8W-30
Back-Up Lamp Switch..................8W-51
Back-Up Lamps.......................8W-51
Battery.............................8W-20
Blower Motor Resistor Block.............8W-42
Brake Lamp Switch....................8W-30
Brake Shift Interlock Solenoid...........8W-30
Brake Warning Indicator Switch..........8W-40
Camshaft Position Sensor...............8W-30
Cargo Lamp..........................8W-44
Center High Mounted Stop Lamp.........8W-51
Center Stack Lamp....................8W-44
Cigar Lighter/Power Outlet..............8W-41
Circuit Breakers (FB)..................8W-11
City Lamps..........................8W-50
Clockspring.....................8W-33, 41, 43
Clutch Interlock Switch.................8W-30
Combination Flasher...................8W-52
Controller Anti-Lock Brake..............8W-35
Crankshaft Position Sensor..............8W-30
Data Link Connector...................8W-30
Decklid Release Switch.................8W-44
Decklid Solenoid......................8W-61
Diode No. 1..........................8W-42
Dome Lamp..........................8W-44
Dome Lamp/Intrusion Sensor............8W-44
Door Ajar Switches....................8W-40
Door Lock Motors.....................8W-61
Engine Coolant Temperature Sensor.......8W-30
Engine Oil Pressure Switch..............8W-30
Engine Starter Motor Relay.............8W-21
Engine Starter Motor..................8W-21
Fog Lamps........................8W-50, 51
Front Fog Lamp Switch.................8W-50
Fuel Injectors........................8W-30
Fuel Pump Module....................8W-30
Fuel Pump Relay......................8W-30
Fuel Tank...........................8W-30
Fuses (FB)...........................8W-11
Fuses (PDC).........................8W-10
Fuse Block...........................8W-11
Fusible Link A11...................8W-20, 21
Grounds.............................8W-15Component Page
Generator...........................8W-20
Glove Box Lamp/Switch.................8W-44
Headlamp Beam Select..............8W-40, 50
Headlamp Leveling Motors..............8W-50
Headlamp Leveling Switch Illumination....8W-50
Headlamp Leveling Switch..............8W-50
Headlamp Switch...................8W-50, 51
Headlamps..........................8W-50
Horns..............................8W-41
Horn Relay..........................8W-41
Horn Switch.........................8W-41
Hood Ajar Switch......................8W-39
Idle Air Control Motor..................8W-30
Ignition Coil.........................8W-30
Ignition Switch.......................8W-10
Indicators...........................8W-40
Indicator Drivers......................8W-40
Inlet Air Temperature Sensor............8W-30
Instrument Cluster....................8W-40
Instrument Panel Drivers...............8W-40
Knock Sensor.........................8W-30
Leak Detection Pump..................8W-30
License Lamps........................8W-51
Manifold Absolute Pressure Sensor........8W-30
Map/Reading Lamps...................8W-44
Multi- Function Switch.........8W-40, 50, 51, 52
Noise Suppressor......................8W-30
Oxygen Sensors.......................8W-30
Park Brake Switch....................8W-40
Park/Neutral Position Switch............8W-51
Park/Turn Signal Lamps................8W-52
Power Distribution Center...............8W-10
Power Mirror Switch...................8W-62
Power Steering Pressure Switch..........8W-30
Powertrain Control Module..............8W-30
PRNDL Lamp........................8W-44
Proportional Evap/Purge Solenoid.........8W-30
Radiator Fan Motor....................8W-42
Radiator Fan Relay....................8W-42
Radio...............................8W-47
Rear Window Defogger Switch...........8W-48
Rear Window Defogger.................8W-48
Remote Keyless Entry Module............8W-39
Repeater Lamps......................8W-52
Seat Belt Switch......................8W-40
Sentry Key Immobilizer Module..........8W-39
Side Marker Lamps....................8W-50
Siren...............................8W-39
Speakers............................8W-47
Splice Information.....................8W-70
Sunroof Control Module................8W-64
Sunroof Motor........................8W-64
PL8W - 02 COMPONENT INDEX 8W - 02 - 1
Page 415 of 1285

FUSES
FUSE NO. AMPS FUSED CIRCUIT FEED CIRCUIT
340A A3 12RD/WT A0 8RD
A2 12PK/BK
A16 14GY 40A
4
630A
A1 14RD
A4 10BK/RD 30A
9
M1 20PK 40A
10
1315A
F1 16DB
1420A
A15 18WT
A14 14RD/WT F62 18RD
15A
18
2220A 2120A
A17 20RD/BK F62 18RD
16A0 8RD
A0 8RD
15A
15
7
19
A0 8RD A0 8RD A0 8RD A0 8RD
A0 8RD
A0 8RD A0 8RD A0 8RD A0 8RD
21
A0 8RD 30A
5A20 12RD/DB
A0 8RD
840A A10 12RD/DG
1211
20 17
- - - -- -
-- -
-- -
-- -
-- - -- -
23-- -
25A F61 16WT/OR A0 8RD
15A F32 18PK/DB A0 8RD
8W - 10 - 4 8W-10 POWER DISTRIBUTIONPL
008W-10PLI01004
Page 435 of 1285

10A 15A 10A
L39 20LB F33 20PK/RD 15A 20A F35 18RD 10AF12 18DB/WT F20 20WT 10A 20A C1 14DG 20A F10 18YL/RDX12 18RD/WT L6 20RD/WT
10A
A31 14BK/WT
A31 14BK/WT
A31 14BK/WT
A22 12BK/OR
A22 12BK/OR
A21 14DB
A21 14DB
A3 12RD/WT
A3 12RD/WT
F39 14PK/LG G5 20DB/WT 10A A22 12BK/ORF25 18TN/LG
10A A21 14DBF15 18DG/WT
5A A3 12RD/WTF9 20RD/BK
10A L4 14VT/WTL44 14VT/RD 10A L4 14VT/WTL43 14VT
10A
C15 12BK/WT C16 20LB/YL
C16 20LB/YL L39 20LB F12 18DB/WT
A22 12BK/OR
A3 12RD/WT
25A F3 12LB/ORF21 14TN
30A
CIRCUIT BREAKERS
C.B. NO. AMPS FUSED CIRCUIT FEED CIRCUIT
RKE
FRONT FOG LAMPS
POWER OPTIONS
AMPS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
FUSE NO.
FUSES
- - -
-- -
FEED CIRCUIT FUSED CIRCUIT
10A
L6 20RD/WT
V6 16DB
V6 16DBA31 14BK/WT
HEATED MIRRORS -- -
1
2
8W - 11 - 4 8W-11 FUSE BLOCK
LHDPL
008W-10PLI01104
Page 436 of 1285

F33 20PK/RD 15A A3 12RD/WT
5A A3 12RD/WTF9 20RD/BK
A22 12BK/OR
A3 12RD/WT
25A F3 12LB/ORF21 14TN
30A
CIRCUIT BREAKERS
C.B. NO. AMPS FUSED CIRCUIT FEED CIRCUIT
HEATED MIRRORS
RKE
POWER OPTIONS
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
FUSES
G5 20DB/WT
20A F35 18RD/YLF15 18DG/WT 10A 10A F25 18TN/LGF20 20WT
10A A22 12BK/OR
A21 14DB
A3 12RD/WT 20A A22 12BK/ORC1 14DG
A22 12BK/OR
A21 14DB F12 18DB/WT 15A 10A A21 14DB
-- --- -- - -
10A L43 14VT L4 14VT/WT
L4 14VT/WT 10A L44 14VT/RD
C16 20LB/YL
10AC15 12BK
C16 20LB/YL
10A
20A F10 18YL/RDX12 18RD/WT L6 20RD/WT
10A
A31 14BK/WT
A31 14BK/WT
A31 14BK/WT
AMPS
1
2
3
4
FUSE NO.FEED CIRCUIT FUSED CIRCUIT
10A
L6 20RD/WT
V6 16DB
V6 16DBA31 14BK/WT
-- -
1
2
PL8W-11 FUSE BLOCK
RHD8W - 11 - 5
PLI01105008W-10
Page 496 of 1285

POWER
DISTRIBUTION
CENTER BLOCK FUSEST-RUN A21BATT A0
10A
FUSE
11
10A
FUSE
1013FUSE15A
30 10 11
3113
4
26
5
MODULE IMMOBILIZER
KEY
SENTRY
B5C1035
D25
20
VT/YL
D25
20
VT/YL
D25
22
VT/YL
D25
22
VT/YL
S217
C104
S104C20
20
2
CONNECTORLINK DATA
S207
G201
Z2
20
BK/LG
Z2
20
BK/LG
M1
20
PK
M1
20
PK
M1
20
PK
S220
S201 S103
G5
20
DB/WT
G5
20
DB/WT
LHD RHD
FUSED
IGNITION
SWITCH
OUTPUT
(ST-RUN)
PCI
BUS
GROUNDFUSED
B(+)
M1
20
PK
(8W-10-2)
(8W-10-3) (8W-11-2)
(8W-11-3) (8W-10-10)(8W-10-7)
(8W-11-10) (8W-11-10)(8W-10-12)
(8W-30-4)
(8W-30-4)
(8W-30-4)(8W-15-8)
(8W-15-8) (8W-11-10)
(8W-10-12) (8W-10-12)
PL8W-39 VEHICLE THEFT SECURITY SYSTEM 8W - 39 - 3
PLI03903008W-10
Page 845 of 1285

²All inputs monitored for proper voltage range.
²All monitored components (refer to the Emission
section for On-Board Diagnostics).
The PCM compares the upstream and downstream
heated oxygen sensor inputs to measure catalytic
convertor efficiency. If the catalyst efficiency drops
below the minimum acceptable percentage, the PCM
stores a diagnostic trouble code in memory.
During certain idle conditions, the PCM may enter
a variable idle speed strategy. During variable idle
speed strategy the PCM adjusts engine speed based
on the following inputs.
²A/C sense
²Battery voltage
²Battery temperature
²Engine coolant temperature
²Engine run time
²Power steering pressure switch
²Vehicle mileage
ACCELERATION MODE
This is a CLOSED LOOP mode. The PCM recog-
nizes an abrupt increase in Throttle Position sensor
output voltage or MAP sensor output voltage as a
demand for increased engine output and vehicle
acceleration. The PCM increases injector pulse width
in response to increased fuel demand.
DECELERATION MODE
This is a CLOSED LOOP mode. During decelera-
tion the following inputs are received by the PCM:
²A/C pressure transducer
²A/C sense
²Battery voltage
²Intake air temperature
²Engine coolant temperature
²Crankshaft position (engine speed)
²Exhaust gas oxygen content (upstream heated
oxygen sensor)
²Knock sensor
²Manifold absolute pressure
²Power steering pressure switch
²Throttle position
²IAC motor control changes in response to MAP
sensor feedback.
The PCM may receive a closed throttle input from
the Throttle Position Sensor (TPS) when it senses an
abrupt decrease in manifold pressure. This indicates
a hard deceleration. In response, the PCM may
momentarily turn off the injectors. This helps
improve fuel economy, emissions and engine braking.
If decel fuel shutoff is detected, downstream oxy-
gen sensor diagnostics is performed.WIDE-OPEN-THROTTLE MODE
This is an OPEN LOOP mode. During wide-open-
throttle operation, the following inputs are received
by the PCM:
²Intake air temperature
²Engine coolant temperature
²Engine speed
²Knock sensor
²Manifold absolute pressure
²Throttle position
When the PCM senses a wide-open-throttle condi-
tion through the Throttle Position Sensor (TPS) it de-
energizes the A/C compressor clutch relay. This
disables the air conditioning system.
The PCM does not monitor the heated oxygen sen-
sor inputs during wide-open-throttle operation except
for downstream heated oxygen sensor and both
shorted diagnostics. The PCM adjusts injector pulse
width to supply a predetermined amount of addi-
tional fuel.
IGNITION SWITCH OFF MODE
When the operator turns the ignition switch to the
OFF position, the following occurs:
²All outputs are turned off, unless 02 Heater
Monitor test is being run. Refer to the Emission sec-
tion for On-Board Diagnostics.
²No inputs are monitored except for the heated
oxygen sensors. The PCM monitors the heating ele-
ments in the oxygen sensors and then shuts down.
SYSTEM DIAGNOSIS
OPERATION
The PCM can test many of its own input and out-
put circuits. If the PCM senses a fault in a major
system, the PCM stores a Diagnostic Trouble Code
(DTC) in memory.
For DTC information see On-Board Diagnostics.
POWER DISTRIBUTION CENTER
The Power Distribution Center (PDC) is located
next to the battery (Fig. 1). The PDC contains the
starter relay, radiator fan relay, A/C compressor
clutch relay, auto shutdown relay, fuel pump relay
and several fuses.
POWERTRAIN CONTROL MODULE
The Powertrain Control Module (PCM) is a digital
computer containing a microprocessor (Fig. 2). The
PCM receives input signals from various switches
and sensors that are referred to as PCM Inputs.
Based on these inputs, the PCM adjusts various
engine and vehicle operations through devices that
are referred to as PCM Outputs.
PCM Inputs:
14 - 24 FUEL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)