vacuum DODGE NEON 2000 Service Owner's Manual

DESCRIPTION AND OPERATION
HEADLAMP SWITCH
The headlamp switch is part of the Multi-Function
Switch. Refer to Group 8J, Turn Signal and Flasher
for the Multi-Function Switch Test, Removal and
Installation procedures.
INSTRUMENT CLUSTER
There are two conventional instrument cluster
assemblies available. The clusters electronically drive
the speedometer, odometer, gauges, and tachometer
(if equipped). Refer to (Fig. 2) and (Fig. 3).
The instrument cluster controls the courtesy
lamps, it receives and sends messages to other mod-
ules via the PCI bus circuit, it controls all the instru-
ment illumination and the chime is also an integral
part of the cluster. The front turn signals are wired
through the cluster and then go to the front lamps.
The reason being that the DRL module is built into
the cluster (if equipped).
All gauges in the electronic clusters are the analog
type gauges. When the ignition switch is moved to
the OFF position, the cluster drives each gauge to its
lowest position. The individual gauges are not servi-
cable and require complete replacement of the cluster
if one or more gauges are inoperable.
One button is used to switch the display from trip
to total mileage. Holding the button when the display
is in the trip mode will reset the trip mileage. This
button is also used to put the cluster in self-diagnos-
tic mode. Refer to Service Procedures, Cluster Self-
Diagnostics in this section. Most of the indicators will
come on briefly for a bulb heck when the ignition is
turned from OFF to ON. All of the LED's are replace-
able.
In the event that the instrument cluster looses
communication with all other modules on the PCI
bus, the cluster will display ªnobusº in the VF dis-
play. The VF display also displays ªDoorº, ªCruiseº,
ªTracº, and odometer trip or total.
If the cluster does not detect voltage on the cour-
tesy lamp circuit, the message ªFUSEº will alternate
with the odometer/trip odometer for 30 seconds after
the ignition is turned on and for 15 seconds after the
vehicle is first moved. The lack of voltage can be due
to the M1 Fused B(+) (IOD) fuse being open, a bad or
missing courtesy lamp bulb, or a circuit problem.
WARNING AND INDICATOR LAMPS
The instrument cluster has warning lamps and
indicators for the following systems:
²Airbag
²Anti-lock Brakes (ABS) if equipped
²Brake warning
²Charging System²Front fog lamps (if equipped)
²High beam indicator
²Low fuel (premium cluster only)
²Low oil pressure
²Malfunction indicator (service engine soon) lamp
²Right and left turn signals
²Seat belt warning
²Security system
²Trac-Off (ABS equipped vehicles only)
The instrument cluster has a Vacuum Fluorescent
(VF) display for the following systems:
²Cruise
²Door (ajar)
²Odometer
²Set (cruise)
²Trac
²Trip
DIAGNOSIS AND TESTING
AIRBAG WARNING SYSTEM
For testing of this system refer to Group 8M, Pas-
sive Restraint Systems.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when the
parking brake is applied with ignition switch turned
to the ON position. The same lamp will also illumi-
nate if one of the two service brake systems fail the
when brake pedal is applied.
To test the system:
²As the ignition switch is turned to the start posi-
tion the lamp should light.
²Turn ignition switch to the ON position and
apply the parking brake. The lamp should light.
If lamp fails to light inspect for:
²A burned out lamp
²Loose, corroded or damaged socket
²A damaged circuit board
²A broken or disconnected wire at the switch
²Defective switch
To test the service brake warning system, refer to
Group 5, Brakes, Hydraulic System Control Valves.
INSTRUMENT CLUSTER LAMPS
Every time the vehicle is switched to the START/
RUN position, the cluster goes through a BULB
CHECK. This tests most of the indicator lamps and
Vacuum Fluorescent (VF) displays. If only one lamp
is out, remove the instrument cluster and replace the
defective bulb or Light Emitting Diode (LED). If
some or all of the lamps fail to light, refer to the
proper Body Diagnostics Procedures Manual.
8E - 2 INSTRUMENT PANEL SYSTEMSPL

(19) Disconnect one left side harness connector at
top left of instrument panel for vanity and rear view
mirrors.
(20) Pull off the hvac control head knobs.
(21) Remove two screws retaining the top front of
the center bezel.
(22) Using a trim stick, gently pry out on the
instrument panel center bezel and remove.
(23) Remove the two retaining screws to the hvac
control head.
(24) Disconnect the one instrument panel wire
harness connector.
(25) Disconnect the one vacuum harness connector.
(26) Pull hvac control head out of instrument
panel, twist 90É and push back through the opening
(Fig. 12). Do not disconnect the control cables.
(27) Disconnect the center console wiring:
²Airbag Control Module (ACM)
²Parking Brake Warning Lamp Switch
²Transmission Range Indicator Lamp
(28) With help on an assistant, pull rearward on
instrument panel assembly and remove from vehicle.
If replacing instrument panel, transfer parts as
necessary.
INSTALLATION
For installation, reverse the above procedures.
Fig. 12 HVAC Control Head
1 ± HVAC CONTROL HEAD
2 ± RADIO
3 ± HVAC CONTROL HEAD HARNESS CONNECTOR
8E - 8 INSTRUMENT PANEL SYSTEMSPL
REMOVAL AND INSTALLATION (Continued)

VEHICLE SPEED CONTROL SYSTEM
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
SPEED CONTROL SYSTEM.................1
SPEED CONTROL SERVO-PCM OUTPUT.......2
SPEED CONTROL SWITCHESÐPCM INPUT....2
STOP LAMP SWITCH......................3
SERVO CABLE...........................3
VACUUM RESERVOIR.....................3VEHICLE SPEED SENSOR..................3
REMOVAL AND INSTALLATION
SPEED CONTROL SERVO...................3
SPEED CONTROL SWITCH..................4
SPEED CONTROL SERVO CABLE.............4
VACUUM RESERVOIR.....................5
DESCRIPTION AND OPERATION
SPEED CONTROL SYSTEM
OPERATION
The speed control system is electronically con-
trolled and vacuum operated. The electronic control
is integrated into the Powertrain Control Module
which is located in the engine compartment. The con-
trols are located on the steering wheel and consist of
five switches. The ON, OFF and SET buttons are
located on the left side of the airbag module. The
RESUME, ACCEL, COAST and CANCEL buttons
are located on the right side of the airbag module
(Fig. 1).
The system is designed to operate at speeds above
25 mph (40 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO
NOT PERMIT MAINTAINING A CONSTANT SPEED,
SUCH AS IN HEAVY TRAFFIC OR ON ROADS THAT
ARE WINDING, ICY, SNOW COVERED, OR SLIP-
PERY.
The speed control can be disengaged manually by:
²Stepping on the brake pedal
²Depressing the OFF switch
²Depressing the CANCEL switch.
The speed control can be disengaged also by any of
the following conditions:
²An indication of Park or Neutral
²The VSS signal increases at a rate of 10 mph
per second (indicates that the co-efficient of friction
between the road surface and tires is extremely low)
²Depressing the clutch pedal.
²Excessive engine rpm (indicates that the trans-
mission may be in a low gear)²The VSS signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
²If the actual speed is not within 20 mph of the
set speed
The previous disengagement conditions are pro-
grammed for added safety.
Fig. 1 Speed Control Switch
1 ± SPEED CONTROL SWITCHES
2 ± RES ACCEL
3 ± CANCEL
4 ± COAST
5 ± SET
6 ± ON/OFF
PLVEHICLE SPEED CONTROL SYSTEM 8H - 1

SPEED CONTROL SERVO-PCM OUTPUT
DESCRIPTION
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The solenoid valve body con-
tains three solenoids:
²Vacuum
²Vent
²Dump
The vacuum chamber contains a diaphragm with a
cable attached to control the throttle linkage.
OPERATION
The PCM controls the solenoid valve body. The
solenoid valve body controls the application and
release of vacuum to the diaphragm of the vacuum
servo. The servo unit cannot be repaired and is ser-
viced only as a complete assembly.
Power is supplied to the servo's by the PCM
through the brake switch. The PCM controls the
ground path for the vacuum and vent solenoids.
The dump solenoid is energized anytime it receives
power. If power to the dump solenoid is interrupted,
the solenoid dumps vacuum in the servo. This pro-
vides a safety backup to the vent and vacuum sole-
noids.
The vacuum and vent solenoids must be grounded
at the PCM to operate. When the PCM grounds the
vacuum servo solenoid, the solenoid allows vacuum
to enter the servo and pull open the throttle plate
using the cable. When the PCM breaks the ground,
the solenoid closes and no more vacuum is allowed to
enter the servo. The PCM also operates the vent sole-
noid via ground. The vent solenoid opens and closes a
passage to bleed or hold vacuum in the servo as
required.
The PCM duty cycles the vacuum and vent sole-
noids to maintain the set speed, or to accelerate and
decelerate the vehicle. To increase throttle opening,
the PCM grounds the vacuum and vent solenoids. To
decrease throttle opening, the PCM removes the
grounds from the vacuum and vent solenoids. When
the brake is released, if vehicle speed exceeds 25
mph to resume, 30 mph to set, and the RES/ACCEL
switch has been depressed, ground for the vent and
vacuum circuits is restored.
SPEED CONTROL SWITCHESÐPCM INPUT
Description
There are two separate switch pods that operate
the speed control system. The steering-wheel-
mounted switches use multiplexed circuits to provide
inputs to the PCM for ON, OFF, RESUME, ACCEL-
ERATE, SET, DECEL and CANCEL modes. Refer tothe owner's manual for more information on speed
control switch functions and setting procedures.
The individual switches cannot be repaired. If one
switch fails, the entire switch module must be
replaced.
Operation
When speed control is selected by depressing the
ON, OFF switch, the PCM allows a set speed to be
stored in RAM for speed control. To store a set speed,
depress the SET switch while the vehicle is moving
at a speed between 25 and 85 mph. In order for the
speed control to engage, the brakes cannot be
applied, nor can the gear selector be indicating the
transmission is in Park or Neutral.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the PCM's RAM.
NOTE: Depressing the OFF switch will erase the
set speed stored in the PCM's RAM.
If, while the speed control is engaged, the driver
wishes to increase vehicle speed, the PCM is pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the RAM when the ACCEL switch is
released. The PCM also has a ªtap-upº feature in
which vehicle speed increases at a rate of approxi-
mately 2 mph for each momentary switch activation
of the ACCEL switch.
The PCM also provides a means to decelerate with-
out disengaging speed control. To decelerate from an
existing recorded target speed, depress and hold the
COAST switch until the desired speed is reached.
Then release the switch. The ON, OFF switch oper-
ates two components: the PCM's ON, OFF input, and
the battery voltage to the brake switch, which powers
the speed control servo.
Multiplexing
The PCM sends out 5 volts through a fixed resistor
and monitors the voltage change between the fixed
resistor and the switches. If none of the switches are
depressed, the PCM will measure 5 volts at the sen-
sor point (open circuit). If a switch with no resistor is
closed, the PCM will measure 0 volts (grounded cir-
cuit). Now, if a resistor is added to a switch, then the
PCM will measure some voltage proportional to the
size of the resistor. By adding a different resistor to
each switch, the PCM will see a different voltage
depending on which switch is pushed.
8H - 2 VEHICLE SPEED CONTROL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

On most vehicles another resistor has been added
to the at rest circuit causing the PCM to never see 5
volts. This was done for diagnostic purposes. If the
switch circuit should open (bad connection) then the
PCM will see the 5 volts and know the circuit is bad.
The PCM will then set an open circuit fault.
STOP LAMP SWITCH
DESCRIPTION
The switch is mounted on the brake pedal mount-
ing bracket under the instrument panel.
OPERATION
Vehicles equipped with the speed control option use
a dual function stop lamp switch. The PCM monitors
the state of the dual function stop lamp switch. Refer
to the Brake section for more information on stop
lamp switch service and adjustment procedures.
The brake switch is equipped with three sets of
contacts, one normally open and the other two nor-
mally closed (brakes disengaged). The PCM sends a
12 volt signal to one of the normally closed contacts
in the brake switch, which is connected to a ground.
With the contacts closed, the 12 volt signal is pulled
to ground causing the signal to go low. The low volt-
age signal, monitored by the PCM, indicates that the
brakes are not applied. When the brakes are applied,
the contacts open, causing the PCM's output voltage
to go high, disengaging the speed control also
grounding the dump solenoid.
The second set of normally closed contacts is sup-
plied battery voltage any time speed control is
selected. From the brake switch, current is routed to
the speed control servo solenoids. The speed control
solenoids (vacuum, vent and dump) are provided this
current any time the speed control is ON and the
brakes are disengaged. When the driver applies the
brakes, the contacts open and current is interrupted
to the solenoids. The normally open contacts are fed
battery voltage. When the brakes are applied, battery
voltage is supplied to the stop lamps.
SERVO CABLE
DESCRIPTION
The speed control servo cable is connected between
the speed control vacuum servo diaphragm and the
throttle body control linkage.
OPERATION
This cable causes the throttle control linkage to
open or close the throttle valve in response to move-
ment of the vacuum servo diaphragm.
VACUUM RESERVOIR
OPERATION
The reservoir stores engine vacuum in the reser-
voir. When engine vacuum drops, as in climbing a
grade while driving, the reservoir supplies the vac-
uum needed to maintain proper speed control opera-
tion. The vacuum reservoir cannot be repaired and
must be replaced if faulty.
VEHICLE SPEED SENSOR
The Vehicle Speed Sensor (VSS) is a pulse genera-
tor mounted to an adapter near the transmission out-
put shaft. The sensor is driven through the adapter
by a speedometer pinion gear. The VSS pulse signal
to the speedometer/odometer is monitored by the
PCM speed control circuitry to determine vehicle
speed and to maintain speed control set speed.
REMOVAL AND INSTALLATION
SPEED CONTROL SERVO
REMOVAL
(1) Disconnect electrical connector from servo (Fig.
2).
(2) Disconnect vacuum hose from servo
(3) Remove 2 nuts retaining cable to servo.
(4) Remove retaining clip pin holding cable to
servo.
Fig. 2 Speed Control Servo
PLVEHICLE SPEED CONTROL SYSTEM 8H - 3
DESCRIPTION AND OPERATION (Continued)

INSTALLATION
(1) Install retaining clip to cable at servo.
(2) Install 2 nuts at cable to servo and servo
bracket, tighten to 7 N´m (60 ins. lbs.).
(3) Connect electrical connector to servo.
(4) Connect vacuum hose to servo
SPEED CONTROL SWITCH
The speed control switches are mounted in the
steering wheel and wired through the clock spring
device under the airbag module (Fig. 1).
WARNING: IF REMOVAL OF AIRBAG MODULE IS
NECESSARY, REFER TO THE RESTRAINT SYS-
TEMS.
REMOVAL
(1) Turn off ignition.
(2) Remove two screws from side of each switch.
(3) Rock switch away from airbag and steering
wheel.
(4) Disconnect two-way electrical connector.
(5) Repeat for the other switch.
INSTALLATION
(1) Install switches.
(2) Connect two-way electrical connector.
(3) Install two screws to the side of each switch.
(4) Install airbag, refer to the Restraint Systems
SPEED CONTROL SERVO CABLE
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the throttle cable cover.
(3) Remove speed control cable from throttle lever
by sliding clasp out of the hole (Fig. 4).
(4) Lift the retaining tab on the throttle cable and
slide cable out of bracket. Lift the retaining tab on
the speed control cable and slide cable out of bracket.
(5) Disconnect electrical connector from servo.
(6) Disconnect vacuum hose from servo
(7) Remove 2 nuts retaining bracket to servo (Fig.
3).
(8) Remove push nuts holding cable housing to
servo.
(9) Remove retaining clip holding cable to servo.
INSTALLATION
(1) Install retaining clip to cable at servo.
(2) Slide cable bell housing over servo mounting
studs.
(3) Install servo mounting studs into bracket.
(4) Install 2 nuts at cable to servo and servo
bracket, tighten to 7 N´m (60 ins. lbs.).
(5) Connect electrical connector to servo.
(6) Connect vacuum hose to servo
(7) Rotate the throttle lever forward to the wide
open position and install speed control cable clasp.
(8) Slide speed control cable into throttle cable
bracket and engage retaining tab. Slide throttle cable
into throttle cable bracket and engage retaining tab.
(9) Install the Throttle cable cover.
(10) Connect the negative battery cable.
Fig. 3 Speed Control Servo
Fig. 4 Speed Control Cable
8H - 4 VEHICLE SPEED CONTROL SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

VACUUM RESERVOIR
REMOVAL
(1) Raise and support vehicle.
(2) Remove screws on top of vacuum reservoir.
(3) Remove vacuum hose.
(4) Remove vacuum reservoir (Fig. 5).
INSTALLATION
(1) Install vacuum reservoir, install screws and
tighten to 5 N.m (44 in. lbs.).
(2) Install vacuum hose.
(3) Lower vehicle.
Fig. 5 Vacuum Reservoir
PLVEHICLE SPEED CONTROL SYSTEM 8H - 5
REMOVAL AND INSTALLATION (Continued)

WINDSHIELD WASHER SYSTEM
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
WINDSHIELD WASHER NOZZLE(S)............8
WINDSHIELD WASHER SYSTEM.............8
DIAGNOSIS AND TESTING
WINDSHIELD WASHER SYSTEM.............9REMOVAL AND INSTALLATION
WINDSHIELD WASHER HOSE................9
WINDSHIELD WASHER NOZZLES.............9
WINDSHIELD WASHER RESERVOIR..........10
WINDSHIELD WASHER PUMP...............10
DESCRIPTION AND OPERATION
WINDSHIELD WASHER NOZZLE(S)
This model is equipped with two hood mounted
washer nozzles. Each nozzle emits two streams into the
wiper pattern (Fig. 1). If the nozzle performance is
unsatisfactory they can be adjusted. To adjust insert a
pin into the nozzle ball and move to proper pattern (Fig.
2). The right and left nozzles are identical.
WINDSHIELD WASHER SYSTEM
All models are equipped with electrically operated
windshield washer pumps. The wash function can be
accessed in the OFF position of the wiper control
switch. Holding the wash button depressed when the
switch is in the OFF position will operate the wipers
and washer motor pump continuously until the
washer button is released. Releasing the button will
stop the washer pump but the wipers will complete
the current wipe cycle. Followed by an average of two
more wipe cycles (61) before the wipers park and the
module turns off.
The electric pump assembly is mounted directly to
the reservoir. A permanently lubricated motor is cou-
pled to a rotor type pump. Fluid, gravity fed from the
reservoir, is forced by the pump through rubber hoses
to the hood mounted nozzles which direct the fluid
streams to the windshield.
The pump and reservoir are serviced as separate
assemblies (Fig. 3).
Fig. 1 Windshield Washer Nozzle - Typical
1 ± HOOD
2 ± ADJUST WITH A PIN
3 ± NOZZLE
4 ± FWD
Fig. 2 Windshield Washer Pattern - Typical
1 ± NOZZLE AIR TARGET
Fig. 3 Windshield Washer Reservoir
1 ± WINDSHIELD WASHER PUMP
2 ± SPEED CONTROL VACUUM RESERVOIR
3 ± WINDSHIELD WASHER HOSE
8K - 8 WINDSHIELD WIPER and WASHER SYSTEMSPL

WINDSHIELD WASHER RESERVOIR
REMOVAL
(1) Raise vehicle on hoist.
(2) Disconnect the wire connector from the reser-
voir pump (Fig. 5).
(3) Disconnect the washer hose at the pump and
drain the reservoir.
(4) Disconnect the vacuum connector to the speed
control vacuum reservoir.
(5) Remove fasteners from reservoir.
(6) Remove the reservoir through fender opening.
If replacing reservoir, the windshield washer pump
and the speed control vacuum reservoir must be
transferred to the new washer reservoir.
(7) Remove two fasteners retaining speed control
vacuum reservoir.
(8) Remove to the windshield washer pump from
the reservoir. Refer to Windshield Washer Pump
Removal and Installation in this section.
INSTALLATION
For installation, reverse the above procedures.
Tighten the reservoir screws to 2.2 to 3.3 N´m (20 to
29 in. lbs.) torque.
WINDSHIELD WASHER PUMP
REMOVAL
(1) Raise vehicle on hoist.
(2) Disconnect the wire connector from the reser-
voir pump.
(3) Disconnect the washer hose at the pump and
drain the reservoir.
(4) Gently pry pump away from reservoir and out
of grommet. Care must be taken not to puncture res-
ervoir (Fig. 6).
(5) Remover rubber grommet from reservoir. If
replacing the pump, discard the old washer pump
grommet. If replacing the reservoir only, reuse the
old washer pump grommet.
INSTALLATION
For installation, reverse the above procedures.
Make sure to use new grommet when installing new
washer pump.
Fig. 5 Windshield Washer Reservoir Remove/Install
Fig. 6 Windshield Washer Pump Remove/Install
1 ± WASHER PUMP
2 ± RUBBER GROMMET
8K - 10 WINDSHIELD WIPER and WASHER SYSTEMSPL
REMOVAL AND INSTALLATION (Continued)

DIAGNOSIS AND TESTING
AIRBAG SYSTEM
(1) Disconnect and isolate the battery negative
cable (Fig. 4).
(2) Connect the DRB llltscan tool to the Data
Link Connector (DLC), located at left side of the
steering column and at the lower edge of the lower
instrument panel (Fig. 5). Ensure that the latest ver-
sion is being used.
(3) Turn the ignition key to ON position. Exit vehi-
cle with the DRB llltscan tool.
(4) After checking that no one is inside the vehicle,
connect the battery negative cable.
(5) Using the DRB llltscan tool, read and record
active Diagnostic Trouble Code (DTC) data.
(6) Read and record any stored DTC's.
(7) Refer to the proper Body Diagnostic Procedures
Manual if any DTC's are found in Step 5 or Step 6.
(8) Erase stored DTC's if there are no active
DTC's. If problems remain, DTC's will not erase.
Refer to the proper Body Diagnostic Procedures Man-
ual to diagnose the problem.If airbag warning
lamp either fails to light, or goes on and stays
on, there is a system malfunction. Refer to the
proper Body Diagnostic Procedures Manual to
diagnose the problem.
SERVICE PROCEDURES
CLEAN UP PROCEDURE
Roll of fold the driver side airbag towards the
steering wheel and tape the airbag module cover over
deployed bag.
Roll or fold the passenger airbag towards the
instrument panel surface and close the door over the
folded bag. Then tape the door shut.
Use a vacuum cleaner to remove any residual pow-
der from the vehicle interior. Work from the outside
in to avoid kneeling or sitting in a contaminated
area. Vacuum the heater and A/C outlets as well. If
the heater or air conditioner was in RECIRC mode at
time of airbag deployment, operate blower motor on
low speed and vacuum powder residue expelled from
the heater and A/C outlets. Multiple vacuum cleaning
may to necessary to decontaminate the interior of the
vehicle.
NOTE: Dispose deployed airbag properly, contact
dealer or government agency for disposal recom-
mendations.
SERVICE OF DEPLOYED AIRBAG MODULE
DRIVER AIRBAG
After a Driver Airbag Module has been deployed
the following components must be replaced because
they cannot be reused. Other driver airbag system
components are replaced if damaged.
²Driver Airbag Module
Fig. 4 Battery Negative Cable Remove/Install
1 ± NEGATIVE CABLE
2 ± NEGATIVE BATTERY POST
Fig. 5 Data Link Connector (DLC) Location
1 ± DATA LINK CONNECTOR (DLC)
2 ± BRAKE PEDAL
PLPASSIVE RESTRAINT SYSTEMS 8M - 3