brake sensor DODGE NEON 2000 Service Workshop Manual

8W-95 SPLICE LOCATIONS
DESCRIPTION AND OPERATION
INTRODUCTION
This section provides illustrations identifying the
general location of the splices in this vehicle. A splice
index is provided. Use the wiring diagrams in each
section for splice number identification. Refer to the
index for proper splice number.
SPLICE LOCATIONS (LHD)
The following index covers all splices shown in the
wiring diagrams. If a splice is not shown in this sec-
tion, a N/S will be in the Fig. column.
Spllice Location Fig.
S102 (Except
Built-Up-
Export)Near Left Headlamp T/O 2
S103 Left Side of Instrument
Panel3
S104 Left Side of Instrument
Panel3
S105
(Built-Up-
Export)Left Side of Instrument
Panel3
S106 Near Left Strut Tower 3
S107 Near A/C Low Pressure
Switch T/O3
S108 Near Controller Anti-Lock
Brake3
S109 Near Power Distribution
Center3
S110 Near Radiator Fan Motor
T/O3
S 111
(Built-Up-
Export)Same as S102 2
S112 Near Back-Up Lamp
Switch T/O3
S113 Near Throttle Position
Sensor T/O3
S114 Near Throttle Position
Sensor T/O3
S116
(Built-Up-
Export)Near C110 T/O 3
S117 Near Right Front Side
Marker or Right Repeater
Lamp T/O2
S118 Near Powertrain Control
Module - C2 T/O3Spllice Location Fig.
S119 Near Radiator Fan Motor
T/O3
S120
(Built-Up-
Export)Near Siren T/O 1
S121 Near Fuel Injector NO. 4
T/O4
S122 Near Engine Oil Pressure
Switch T/O5
S123 Near Crankshaft Position
Sensor T/O5
S125 Near Manifold Absolute
Pressure Sensor T/O4
S129 (2.0L) Near Noise Suppressor
T/O5
S130 Near Ignition Coil T/O 5
S131 Near Left Headlamp T/O 2
S132 Near Left Strut Tower 3
S141 Near High Note Horn T/O N/S
S142 Near High Note Horn T/O N/S
S201 Near Right Instrument
Panel Speaker T/O6
S202 Near C202 and C203
T/O6
S203 Near C202 and C203
T/O6
S204 In C202 and C203 T/O 6
S205 Near C202 and C203
T/O6
S206 Near Center of
Instrument Panel6
S207 Near Center of
Instrument Panel6
S208 Near Instrument Cluster
T/O6
PL8W - 95 SPLICE LOCATIONS 8W - 95 - 1

SPLICE LOCATIONS (RHD)
The following index covers all splices shown in the
wiring diagrams. If a splice is not shown in this sec-
tion, a N/S will be in the Fig. column.
Spllice Location Fig.
S103 Near C104 and C103
T/O19
S104 In Data Link Connector
T/O19
S105 Near Grommet 19
S106 Near Left Strut Tower 16
S107 Near Brake Warning
Indicator Switch T/O16
S108 In Controller Anti-Lock
Brake T/O16
S109 Near Power Distribution
Center16
S110 Near Radiator Fan Motor
T/O16
S111 Near Left Headlamp T/O 15
S112 Near Left Strut Tower 16
S113 Near Throttle Position
Sensor T/O16
S114 Near Idle Air Control
Motor T/O16
S116 Near C110 T/O 16
S117 Near Repeater Lamp T/O 15
S118 Near Powertrain Control
Module - C2 T/O16
S119 Near A/C High Pressure
Switch T/O16
S120 Near Siren T/O 14
S121 Near Fuel Injector NO. 4
T/O17
S122 Near Engine Oil Pressure
Switch T/O18
S123 Near Crankshaft Position
Sensor T/O18
S125 Near Manifold Absolute
Pressure Sensor T/O17
S129 (2.0L) Near Noise Suppressor
T/O18
S130 Near Ignition Coil T/O 18
S131 Right Front of Engine
Compartment15
S132 Near Left Strut Tower 16Spllice Location Fig.
S141 Near High Note Horn T/O N/S
S142 Near High Note Horn T/O N/S
S201 Near Left Instrument
Panel Speaker20
S202 Left Side of Instrument
Panel20
S203 Left Side of Instrument
Panel20
S204 Near C202 T/O 20
S205 Left Side of Instrument
Panel20
S206 Left Side of Instrument
Panel20
S207 Near Instrument Cluster
T/O20
S208 Near Instrument Cluster
T/O20
S209 Near Brake Shift
Interlock Solenoid T/ON/S
S211 Near Right Instrument
Panel Speaker T/O20
S212 Near Instrument Cluster
T/O20
S213 Near Instrument Cluster
T/O20
S214 Near Instrument Cluster
T/O20
S215 Near Right Instrument
Panel Speaker T/O20
S216 Near Right Instrument
Panel Speaker T/O20
S217 Near Right Instrument
Panel Speaker T/O20
S218 Near Right Instrument
Panel Speaker T/O20
S219 Near Right Instrument
Panel Speaker T/O20
S220 Near Right Instrument
Panel Speaker T/O20
S221 Near Right Instrument
Panel Speaker T/O20
PL8W - 95 SPLICE LOCATIONS 8W - 95 - 13
DESCRIPTION AND OPERATION (Continued)

(4) Discharge air conditioning system, if equipped.
Refer to Group 24, Heating and Air Conditioning for
procedure.
(5) Disconnect the following: air intake duct at
intake manifold, throttle cables, electrical connectors
from throttle body and air cleaner housing.
(6) Remove air cleaner housing assembly.
(7) Remove upper radiator hose and fan module.
Refer to Group 7, Cooling System for procedure.
(8) Remove lower radiator hose.
(9) Disconnect automatic transmission cooler lines
and plug, if equipped.
(10) Disconnect shift linkage, electrical connectors,
and clutch cable, if equipped with manual transaxle.
(11) Disconnect engine wiring harness.
(12) Disconnect positive cable from Power Distri-
bution Center (PDC) and ground wire from vehicle
body.
(13) Disconnect ground wire from the vehicle body-
to-engine at the right side strut tower.
(14) Disconnect heater hoses.
(15) Disconnect vacuum hose from brake booster.
(16) Disconnect coolant reserve/recovery hose.
(17) Remove accessory drive belts. Refer to Group
7, Cooling System for procedure.
(18) Remove power steering pump and reservoir
and set them aside.
(19) Hoist vehicle and remove right inner splash
shield.
(20) Drain engine oil.
(21) Remove front wheels.
(22) Remove axle shafts. Refer to Group 3, Differ-
ential and Driveline for procedure.
(23) Disconnect exhaust system from manifold.
(24) Disconnect the downstream oxygen sensor
connector.
(25) Remove lower engine torque strut.
(26) Remove structural collar. Refer to procedure
in this section.
(27) Lower vehicle and remove A/C compressor.
(28) Raise vehicle enough to allow engine dolly
and cradle, Special Tools 6135 and 6710 to be
installed under vehicle.
(29) Loosen engine support posts to allow move-
ment for positioning onto engine locating holes and
flange on the engine bedplate. Lower vehicle and
position cradle until the engine is resting on support
posts (Fig. 26). Tighten mounts to cradle frame. This
will keep support posts from moving when removing
or installing engine and transmission.
(30) Install safety straps around the engine to cra-
dle (Fig. 26). Tighten straps and lock them into posi-
tion.
WARNING: Safety straps MUST be used.(31) Raise vehicle enough to see if straps are tight
enough to hold cradle assembly to engine.
(32) Lower vehicle so weight of the engine and
transmission ONLY is on the cradle assembly.
(33) Remove the upper engine torque strut.
(34) Remove right and left engine and transaxle
mount through bolts (Fig. 24) and (Fig. 25).
(35) Raise vehicle slowly until body is approxi-
mately 15 cm (6 in.) above normal engine mounting
locations.
(36) Remove generator, lower bracket, and upper
mounting bolt.
(37) Continue raising vehicle slowly until engine/
transaxle assembly clears engine compartment. It
may be necessary to move the engine/transmission
assembly with the cradle to allow for removal around
body flanges.
INSTALLATION
(1) Position engine and transmission assembly
under vehicle and slowly lower the vehicle over the
engine/transaxle assembly until vehicle is within 15
cm (6 in.) of engine mounting locations.
(2) Install generator, lower bracket, and adjusting
bolt.
(3) Continue lowering vehicle until engine/tran-
saxle aligns to mounting locations. Install mounting
bolts at the right and left engine/transaxle mounts
(Fig. 24) and (Fig. 25). Tighten bolts to 118 N´m (87
ft. lbs.).
(4) Install upper engine torque strut. Refer to pro-
cedure in this section.
(5) Remove safety straps from engine/transaxle
assembly. Slowly raise vehicle enough to remove the
engine dolly and cradle.
(6) Install axle shafts. Refer to Group 3, Differen-
tial and Driveline for procedure.
(7) Install structural collar. Refer to procedure in
this section tightening sequence.
Fig. 24 Right Mount Through Bolt
1 ± BOLT
2 ± RIGHT ENGINE MOUNT
3 ± ENGINE MOUNT BRACKET
9 - 26 2.0L SOHC ENGINEPL
REMOVAL AND INSTALLATION (Continued)

(27) Start engine and run until operating temper-
ature is reached.
(28) Ensure engine is properly positioned. Refer to
Torque Struts in this section for adjustment proce-
dure.
(29) Adjust transmission linkage, if necessary.
INTAKE MANIFOLD
REMOVAL
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE SERVICING FUEL SYSTEM COMPONENTS.
SERVICE VEHICLES IN WELL VENTILATED AREAS
AND AVOID IGNITION SOURCES. NEVER SMOKE
WHILE SERVICING THE VEHICLE.
(1) Disconnect negative cable from battery.
(2) Remove the inlet air duct from intake manifold
to throttle body.
(3) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System for procedures.
WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSE TO CATCH ANY GASOLINE SPILLAGE
(4) Disconnect fuel supply line quick connect at the
fuel tube assembly. Refer to Group 14, Fuel System
for procedures.
(5) Remove fuel rail assembly attaching screws
and remove fuel rail assembly from engine. Cover
injector holes with suitable covering.
CAUTION: Do not set fuel injectors on their tips,
damage may occur to the injectors
(6) Disconnect brake booster hose (Fig. 27) and
PCV hose (Fig. 28) from intake manifold.
(7) Disconnect Manifold Absolute Pressure (MAP)
sensor electrical connector (Fig. 29).
(8) Disconnect knock sensor electrical connector
(Fig. 30).
(9) Disconnect wiring at starter.
(10) Remove the intake manifold to lower support
bracket bolts (Fig. 31).
(11) Remove intake manifold screws and washers.
Discard the fasteners. Remove intake manifold.
INSTALLATION
Before installing manifold. Clean all mating sur-
faces. Replace all O-ring gaskets with new gaskets
(Fig. 33). All intake manifold fasteners and washers
are to be discarded andNEWfasteners and washers
are to be used.(1) Install intake manifold onto cylinder head and
tighten fasteners to 12 N´m (105 in. lbs.) in sequence
shown in (Fig. 32).
Fig. 27 Brake Booster Hose
Fig. 28 PCV Hose
9 - 28 2.0L SOHC ENGINEPL
REMOVAL AND INSTALLATION (Continued)

(2) Install intake manifold to lower support
bracket bolts (Fig. 31). Tighten bolts to 11 N´m (95
in. lbs.).
(3) Remove covering from fuel injector holes and
insure the holes are clean. Install fuel rail assembly
to intake manifold. Tighten screws to 23 N´m (200 in.
lbs.).
(4) Connect PCV and brake booster hoses.
(5) Inspect quick connect fittings for damage,
replace if necessary Refer to Group 14, Fuel System
for procedure. Apply a light amount of clean engine
oil to fuel inlet tube. Connect fuel supply hose to fuel
rail assembly. Check connection by pulling on connec-
tor to insure it locked into position.
(6) Connect Manifold Absolute Pressure (MAP)
Sensor wiring connector (Fig. 29).(7) Connect knock sensor connector, and wiring at
starter.
(8) Install inlet air duct to intake manifold and
throttle body. Tighten clamp to 3 N´m (30 in. lbs.).
(9) Connect negative cable to battery.
(10) With the DRB scan tool use ASD Fuel System
Test to pressurize system to check for leaks.
Fig. 29 MAP Sensor
Fig. 30 Knock Sensor
1 ± KNOCK SENSOR
2 ± STARTER MOTOR
Fig. 31 Intake Manifold Lower Supports
1 ± BOLT
2 ± BRACKET
3 ± BRACKET
4 ± BOLT
Fig. 32 Intake Manifold Tightening Sequence
PL2.0L SOHC ENGINE 9 - 29
REMOVAL AND INSTALLATION (Continued)

FUEL INJECTION SYSTEM
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
INJECTION SYSTEM......................22
MODES OF OPERATION...................22
SYSTEM DIAGNOSIS......................24
POWER DISTRIBUTION CENTER............24
POWERTRAIN CONTROL MODULE...........24
PCM GROUND...........................26
5 VOLT SUPPLYÐPCM OUTPUT.............26
8-VOLT SUPPLYÐPCM OUTPUT.............26
FUEL CORRECTION or ADAPTIVE MEMORIES . . 26
PROGRAMMABLE COMMUNICATIONS
INTERFACE (PCI) BUS...................27
AIR CONDITIONING PRESSURE
TRANSDUCERÐPCM INPUT..............27
AUTOMATIC SHUTDOWN (ASD) SENSEÐ
PCM INPUT...........................27
BATTERY VOLTAGEÐPCM INPUT............28
BRAKE SWITCHÐPCM INPUT...............28
CAMSHAFT POSITION SENSORÐPCM INPUT . . 28
CLUTCH INTERLOCK/UPSTOP SWITCH.......29
CRANKSHAFT POSITION SENSORÐPCM
INPUT................................30
ENGINE COOLANT TEMPERATURE
SENSORÐPCM INPUT...................30
FUEL LEVEL SENSORÐPCM INPUT..........31
HEATED OXYGEN SENSOR (O2 SENSOR)Ð
PCM INPUT...........................32
IGNITION CIRCUIT SENSEÐPCM INPUT......34
INLET AIR TEMPERATURE SENSORÐPCM
INPUT................................34
KNOCK SENSORÐPCM INPUT..............34
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐPCM INPUT...................35
POWER STEERING PRESSURE SWITCHÐ
PCM INPUT...........................35
SENSOR RETURNÐPCM INPUT.............35
SPEED CONTROLÐPCM INPUT.............36
SCI RECEIVEÐPCM INPUT.................36
PARK/NEUTRAL POSITION SWITCHÐPCM
INPUT................................36
THROTTLE POSITION SENSORÐPCM INPUT . . 36VEHICLE SPEED SIGNAL (VSS)ÐPCM INPUT . . 37
AIR CONDITIONING CLUTCH RELAYÐPCM
OUTPUT..............................38
AUTOMATIC SHUTDOWN RELAYÐPCM
OUTPUT..............................38
CHARGING SYSTEM INDICATOR LAMPÐPCM
OUTPUT..............................38
FUEL PUMP RELAYÐPCM OUTPUT..........38
PROPORTIONAL PURGE SOLENOIDÐPCM
OUTPUT..............................39
GENERATOR FIELDÐPCM OUTPUT..........39
IDLE AIR CONTROL MOTORÐPCM OUTPUT . . . 39
DATA LINK CONNECTOR...................40
FUEL INJECTORSÐPCM OUTPUT...........40
IGNITION COILÐPCM OUTPUT..............40
MALFUNCTION INDICATOR (CHECK ENGINE)
LAMPÐPCM OUTPUT...................41
SPEED CONTROLÐPCM INPUT.............41
SCI RECEIVEÐPCM OUTPUT...............41
TACHOMETERÐPCM OUTPUT..............42
TORQUE CONVERTOR CLUTCH SOLENOIDÐ
PCM OUTPUT..........................42
REMOVAL AND INSTALLATION
THROTTLE BODY........................42
THROTTLE POSITION SENSOR.............43
IDLE AIR CONTROL MOTOR................43
MAP SENSOR...........................44
POWERTRAIN CONTROL MODULE (PCM).....44
UPSTREAM HEATED OXYGEN SENSOR......45
DOWNSTREAM HEATED OXYGEN SENSOR
1/2 ..................................46
AIR CLEANER BOX.......................46
AIR CLEANER ELEMENT...................47
ENGINE COOLANT TEMPERATURE SENSOR . . . 47
VEHICLE SPEED SENSOR.................47
KNOCK SENSOR.........................48
SPECIFICATIONS
VECI LABEL.............................49
TORQUE...............................49
SPECIAL TOOLS
FUEL..................................49
PLFUEL SYSTEM 14 - 21

²Air Conditioning Controls
²Battery Voltage
²Inlet Air/Battery Temperature Sensor
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Engine Coolant Temperature Sensor
²Fuel Level Sensor
²Ignition Switch
²Inlet Air/Intake Air Temperature Sensor
²Knock Sensor
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensors
²Power Steering Pressure Switch²SCI Receive
²Speed Control Switches
²Throttle Position Sensor
²Transmission Park/Neutral Switch (automatic
transmission)
²Vehicle Speed Sensor
PCM Outputs:
²Air Conditioning WOT Relay
²Auto Shutdown (ASD) Relay
²Charging Indicator Lamp
²Data Link Connector
²Proportional Purge Solenoid
²EGR Solenoid
²Fuel Injectors
²Fuel Pump Relay
²Generator Field
²Idle Air Control Motor
²Ignition Coils
²Malfunction Indicator (Check Engine) Lamp
²Radiator Fan Relay
²Speed Control Solenoids
²Tachometer
²Torque Convertor Clutch Solenoid
Based on inputs it receives, the PCM adjusts fuel
injector pulse width, idle speed, ignition spark
advance, ignition coil dwell and EVAP canister purge
operation. The PCM regulates the cooling fan, air
conditioning and speed control systems. The PCM
changes generator charge rate by adjusting the gen-
erator field. The PCM also performs diagnostics.
The PCM adjusts injector pulse width (air-fuel
ratio) based on the following inputs.
²Battery voltage
²Coolant temperature
²Inlet Air/Intake air temperature
²Exhaust gas content (oxygen sensor)
²Engine speed (crankshaft position sensor)
²Manifold absolute pressure
²Throttle position
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Coolant temperature
²Inlet Air/Intake air temperature
²Engine speed (crankshaft position sensor)
²Knock sensor
²Manifold absolute pressure
²Throttle position
²Transmission gear selection (park/neutral
switch)
The PCM also adjusts engine idle speed through
the idle air control motor based on the following
inputs.
²Air conditioning sense
²Battery voltage
²Battery temperature
²Brake switch
Fig. 1 Power Distribution Center (PDC)
Fig. 2 Powertrain Control Module (PCM)
1 ± PCM
PLFUEL SYSTEM 14 - 25
DESCRIPTION AND OPERATION (Continued)

BATTERY VOLTAGEÐPCM INPUT
OPERATION
In order for the PCM to operate, it must be sup-
plied with battery voltage and ground. The PCM
monitors the direct battery feed input to determine
battery charging rate and to control the injector ini-
tial opening point. It also has back-up RAM memory
used to store Diagnostic Trouble Codes (supply work-
ing DTCs). Direct battery feed is also used to perform
key-OFF diagnostics and to supply working voltage
to the controller for OBDII.
The five and eight volt regulators are protected
from shorts to ground. This protection allows diag-
nostics to be performed should the five volt power
supply become shorted to ground at any of the sen-
sors. A short to ground in the five volt power supply
will cause a ªno-startº situation. There is a Diagnos-
tic Trouble Code (DTC) if the five-volt power supply
becomes shorted to ground. Refer to the Diagnostic
Procedures Manual for more details on any on-board
diagnostic information.
If battery voltage is low the PCM will increase
injector pulse width (period of time that the injector
is energized).
The direct battery feed to the PCM is used as a
reference point to sense battery voltage.
Effect on Fuel Injectors
Fuel injectors are rated for operation at a specific
voltage. If the voltage increases, the plunger will
open faster and further (more efficient) and con-
versely, if voltage is low the injector will be slow to
open and will not open as far. Therefore, if sensed
battery voltage drops, the PCM increases injector
pulse-width to maintain the same volume of fuel
through the injector.
Charging
The PCM uses sensed battery voltage to verify that
target charging voltage (determined by Battery Tem-
perature Sensor) is being reached. To maintain the
target charging voltage, the PCM will full field the
generator to 0.5 volt above target then turn OFF to
0.5 volt below target. This will continue to occur up
to a 100 Hz frequency, 100 times per second.
BRAKE SWITCHÐPCM INPUT
OPERATION
When the brake switch is activated, the PCM
receives an input indicating that the brakes are
being applied. The brake switch is mounted on the
brake pedal support bracket.
CAMSHAFT POSITION SENSORÐPCM INPUT
DESCRIPTION
The camshaft position sensor attaches to the rear
of the cylinder head. The PCM determines fuel injec-
tion synchronization and cylinder identification from
inputs provided by the camshaft position sensor (Fig.
3) and crankshaft position sensor. From the two
inputs, the PCM determines crankshaft position.
OPERATION
The PCM sends approximately 8 volts to the hall
affect sensor. This voltage is required to operate the
hall effect chip and the electronics inside the sensor.
A ground for the sensor is provided through the sen-
sor return circuit. The input to the PCM occurs on a
5 volt output reference circuit.
A target magnet attaches to the rear of the cam-
shaft and indexes to the correct position. The target
magnet has four different poles arranged in an asym-
metrical pattern (Fig. 4). As the target magnet
rotates, the camshaft position sensor senses the
change in polarity (Fig. 5). The sensor output switch
switches from high (5.0 volts) to low (0.5 volts) as the
target magnet rotates. When the north pole of the
target magnet passes under the sensor, the output
switches high. The sensor output switches low when
the south pole of the target magnet passes under-
neath.
The sensor also acts as a thrust plate to control
camshaft endplay.
Fig. 3 Camshaft Position SensorÐSOHC
14 - 28 FUEL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

CLUTCH INTERLOCK/UPSTOP SWITCH
DESCRIPTION
The clutch interlock/upstop switch is an assembly
consisting of two switches: an engine starter inhibit
switch (interlock) and a clutch pedal upstop switch
(Fig. 6). The switch assembly is located in the clutch/
brake pedal bracket assembly (Fig. 7), each switch
being fastened by four plastic wing tabs.
OPERATION
Clutch Interlock Switch
The clutch interlock switch prevents engine starter
operation and inadvertent vehicle movement with the
clutch engaged and the transaxle in gear.
The switch is open while the clutch pedal is at
rest. When the clutch pedal is fully depressed, the
pedal blade contacts and closes the switch, sending a
Fig. 4 Target MagnetÐTypical
1 ± CAM MAGNET/TARGET
2 ± CAMSHAFT POSITION SENSOR
Fig. 5 Target Magnet Polarity
1 ± TARGET MAGNET
Fig. 6 Clutch Interlock/Upstop Switch
1 ± UPSTOP SWITCH
2 ± INTERLOCK SWITCH
3 ± CONNECTOR
Fig. 7 Clutch/Brake Pedal Bracket Assembly
1 ± UPSTOP SWITCH
2 ± CLUTCH PEDAL
3 ± INTERLOCK SWITCH
4 ± CONNECTOR
PLFUEL SYSTEM 14 - 29
DESCRIPTION AND OPERATION (Continued)

The sensor return circuit connects to internal ground
circuits within the Powertrain Control Module
(PCM).
SPEED CONTROLÐPCM INPUT
OPERATION
The speed control system provides five separate
voltages (inputs) to the Powertrain Control Module
(PCM). The voltages correspond to the ON, OFF,
SET, RESUME, CANCEL, and COAST.
The speed control ON voltage informs the PCM
that the speed control system has been activated.
The speed control SET voltage informs the PCM that
a fixed vehicle speed has been selected. The speed
control RESUME voltage indicates the previous fixed
speed is requested. The speed control CANCEL volt-
age tells the PCM to deactivate but retain set speed
in memory (same as depressing the brake pedal). The
speed control OFF voltage tells the PCM that the
speed control system has deactivated.
Inputs Required for Operation
The inputs required by the PCM to operate the
Speed Control System include:
²Speed Control switches
²Brake switch
²Park/Neutral switch
²Vehicle speed signal
²Engine speed
²CCD bussed message from TCM
SCI RECEIVEÐPCM INPUT
OPERATION
SCI Receive is the serial data communication
receive circuit for the DRB scan tool. The PowertrainControl Module (PCM) receives data from the DRB
through the SCI Receive circuit.
PARK/NEUTRAL POSITION SWITCHÐPCM
INPUT
DESCRIPTION
The park/neutral position switch is located on the
automatic transaxle housing (Fig. 19).
OPERATION
Manual transaxles do not use park/neutral
switches. The switch provides an input to the PCM to
indicate whether the automatic transaxle is in Park/
Neutral, or a drive gear selection. This input is used
to determine idle speed (varying with gear selection)
and ignition timing advance. The park/neutral input
is also used to cancel vehicle speed control. The park/
neutral switch is sometimes referred to as the neu-
tral safety switch.
The PCM delivers 8.5 volts to the center terminal
of the Park/Neutral switch. When the gear shift lever
is moved to either the Park or the Neutral position,
the PCM receives a ground signal from the Park/
Neutral switch. With the shift lever positioned in
Drive or Reverse, the Park/Neutral switch contacts
open, causing the signal to the PCM to go high.
THROTTLE POSITION SENSORÐPCM INPUT
DESCRIPTION
The throttle position sensor mounts to the side of
the throttle body (Fig. 20).
The Throttle Position Sensor (TPS) connects to the
throttle blade shaft. The TPS is a variable resistor
that provides the PCM with an input signal (voltage).
The signal represents throttle blade position. As the
Fig. 18 Power Steering Pressure Switch
1 ± POWER STEERING PRESSURE SWITCH
Fig. 19 Park/Neutral Switch
1 ± PARK/NEUTRAL SWITCH
2 ± TRANSAXLE HOUSING
14 - 36 FUEL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)