1997 DODGE NEON service

Downloaded from www.Manualslib.com manuals search engine WHEEL SPEED SENSORS
There are four wheel speed sensors, one at each
wheel. The sensors use a tone wheel to determine
wheel speed. Input to the Controller Anti Lock Brake
(CAB) is done on the following circuits. All of these
circuits are a twisted pair.
B8 and B9 for the left front wheel (cavity 8 and
cavity 9).
B6 and B7 for the right front wheel (cavity 6 and
cavity 7).
B3 and B4 for the left rear wheel (cavity 3 and cav-
ity 4).
B1 and B2 for the right rear wheel (cavity 1 and
cavity 2).
BRAKE SWITCH INPUT
Circuit L50 is an input to the Controller Anti Lock
Brake (CAB). The L50 connects to cavity 13 of the
CAB connector. Circuit L50 is spliced in with the
stop lamps and is used to provide the CAB with
information on when the brakes are being applied.
DATA LINK CONNECTOR
Circuit D21 is used for diagnostics of a fault with
the ABS system. It is spliced in with the Powertrain
Control Module (PCM) circuits and used as an output
from the Controller Anti Lock Brake (CAB). Circuit
D21 connects to cavity 51 of the CAB connector.
HELPFUL INFORMATION
²Check the 15 amp fuse located in cavity 10 of
the fuse block.
²Check the 40 amp fuse located in the PDC.
²Check for a good ground at the left headlamp
ground.
²Check the case ground on the CAB
²Refer to the appropriate section of the service
manual, or the Diagnostic Test Procedures Manual.
PL8W - 35 ANTI-LOCK BRAKES 8W - 35 - 7
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine 8W-40 INSTRUMENT CLUSTER
INDEX
page page
DESCRIPTION AND OPERATION
AIRBAG WARNING LAMP.................. 8
ANTI-LOCK WARNING LAMP............... 9
BRAKE WARNING INDICATOR LAMP......... 8
CHARGE INDICATOR LAMP................ 8
ENGINE COOLANT TEMPERATURE GAUGE . . . 7
FUEL GAUGE........................... 7
HEADLAMP ON CHIME.................... 8
HELPFUL INFORMATION.................. 9
HIGH BEAM INDICATOR LAMP.............. 8
INSTRUMENT CLUSTER.................. 7KEY-IN CHIME.......................... 8
LOW FUEL LAMP........................ 8
LOW OIL PRESSURE LAMP................ 8
ODOMETER............................ 8
RIGHT AND LEFT TURN
SIGNAL INDICATORS................... 8
SEAT BELT WARNING INDICATOR........... 8
SERVICE ENGINE SOON LAMP............. 8
SPEEDOMETER......................... 7
TACHOMETER.......................... 7
DESCRIPTION AND OPERATION
INSTRUMENT CLUSTER
The Instrument Cluster, located on the right side
of the instrument panel, provides the operator with
gauges and warning lamps relating to vehicle opera-
tion. All gauges in the standard and optional cluster
are magnetic type and logic driven.
Battery voltage for the clusters warning lamps and
gauges is provided on the G5 circuit. This circuit con-
nects from the fuse block and is protected bya5amp
fuse located in cavity 11. The cluster is powered only
when the ignition switch is in the START or RUN
position. The cluster is also powered on initial driv-
er's door opening.
Illumination lamps, internal to the cluster, receive
battery voltage on the E2 circuit from the 4 amp fuse
located in cavity 12 of the fuse block. This circuit is
HOT only when the headlamp switch is in the ON
position. Grounding for the cluster is provided on the
Z3 circuit and terminates at the instrument panel
left center support.
The M1 circuit also feeds the cluster through a 10
amp fuse in the Power Distribution Center (PDC).
This fuse is HOT at all times and also used to power
the underhood lamp, and the interior lamps. The
fuse is also lifted OPEN during vehicle shipping to
reduce battery draw.
SPEEDOMETER
The speedometer and odometer receive their infor-
mation on the G7 circuit from the Vehicle Speed Sen-
sor (VSS) on manual and 3±spd automatic
transmission applications. The G7 circuit also pro-
vides a signal to the Powertrain Control Module
(PCM).Logic internal to the instrument cluster adjusts the
position of the gauge pointer to the correct vehicle
speed using the signal on the G7 circuit.
TACHOMETER
The tachometer is connected to the Powertrain
Control Module (PCM) on the G21 circuit. It uses
solid state circuity to decode the ignition pulses
received from the PCM to adjust the gauge pointer to
the proper position.
ENGINE COOLANT TEMPERATURE GAUGE
The temperature gauge is connected to the engine
coolant temperature sensor on the G20 circuit. The
engine coolant temperature sensor for the gauge is a
combination unit. One side of the unit is used for the
Powertrain Control Module (PCM) and the other side
for the cluster. The sending unit is case grounded to
the engine.
The logic driven gauge moves in response to the
measured resistance of the engine coolant tempera-
ture sending unit.
FUEL GAUGE
The fuel level gauge is connected to the fuel pump
module on the G4 circuit. The fuel pump module con-
tains the fuel pump and a variable resistor for the
gauge. Grounding for the fuel pump module is pro-
vided on the Z2 circuit and terminates at the left
rear wheel house.
The logic driven gauge moves in response to the
measured resistance of the fuel tank sending unit.
The fuel level sensor contains a variable resistor.
As the position of the float arm on the level sensor
changes, the resistor changes the current flow
through the fuel gauge circuit. A change in current
flow alters the magnetic field in the fuel gauge which
changes the pointer position.
PL8W - 40 INSTRUMENT CLUSTER 8W - 40 - 7

Downloaded from www.Manualslib.com manuals search engine ODOMETER
The speedometer and odometer receive their infor-
mation on the G7 circuit from the Vehicle Speed Sen-
sor (VSS) on vehicles equipped with the manual or
3±spd automatic transmission. This circuit also pro-
vides a signal to the Powertrain Control Module
(PCM).
Logic internal to the cluster steps the odometer at
a high rate to indicate the proper mileage.
SERVICE ENGINE SOON LAMP
The Service Engine Soon lamp illuminates when
the ignition switch is in the ON position and prior to
starting the vehicle. The lamp will turn off after the
vehicle is started.
If while the vehicle is running a problem is
detected in the engine control system the lamp is
illuminated. This is accomplished by the Powertrain
Control Module (PCM) grounding the G3 circuit.
SEAT BELT WARNING INDICATOR
The fasten seat belt indicator is used with the
warning chime to indicate to the operator to fasten
the seat belt. There is a switch located in the drivers
side B-pillar that is normally OPEN with the seat
belt buckled.
If the seat belt is not buckled the switch CLOSES
and a ground path is completed from the G10 circuit
to the Z1 circuit. This will illuminate the lamp in the
instrument cluster.
When the ignition switch is moved to the START
position the lamp will illuminate. Logic internal to
the instrument cluster determines the length of time.
LOW FUEL LAMP
The low fuel lamp is used to indicate to the opera-
tor that the fuel level is below a predetermined level.
This lamp is logic driven by the instrument cluster.
When the instrument cluster determines a low fuel
condition based on an input from the fuel tank gauge
level sending unit (circuit G4) it illuminates the
lamp.
HEADLAMP ON CHIME
The headlamp ON chime is used to indicate to the
operator that the headlamps or parking lamps are
ON when the drivers door is OPEN. If the lamps are
ON and the drivers door is opened, a ground path is
completed from the G26 circuit at the cluster,
through the headlamp switch, to the G16 circuit and
ending at the door ajar switch. The door ajar switch
is case grounded.
KEY-IN CHIME
The key-in chime is used to indicate to the opera-
tor that the key is in the ignition with the driversdoor OPEN. If the key is in the ignition and the driv-
ers door is OPEN, a ground path is completed from
the G26 circuit at the cluster, through the CLOSED
key-in switch, to the G16 circuit and terminating at
the door ajar switch which is case grounded.
CHARGE INDICATOR LAMP
The Charge Indicator lamp is used to alert the
operator that the charging system voltage has fallen
below the normal operating range. This circuit is con-
trolled by the Powertrain Control Module (PCM).
When the PCM determines a problem, it grounds the
G12 circuit.
AIRBAG WARNING LAMP
The Airbag Warning lamp is used to alert the oper-
ator of a problem with the Airbag system. The lamp
is illuminated when the Airbag Control Module
(ACM) grounds the R41 circuit. Refer to the appro-
priate section of the Service Manual or Diagnostic
Test Procedures Manual to diagnosis this system.
LOW OIL PRESSURE LAMP
The low oil pressure lamp is used to indicate to the
operator that the engine oil pressure has dropped
below a predetermined pressure. Power for the lamp
is provided on the G5 circuit which also powers the
other warning lamps.
When the oil pressure is low the normally OPEN
oil pressure switch CLOSES completing a path to
ground on circuit G6. The oil pressure switch is case
grounded to the engine block.
HIGH BEAM INDICATOR LAMP
The High Beam Indicator Lamp is used to indicate
to the operator that the high beam headlamps are
ON. Power is supplied to the cluster on the L3 cir-
cuit. Ground is provided on the Z3 circuit.
Circuit L3 connects from the headlamp dimmer
switch to the instrument cluster.
RIGHT AND LEFT TURN SIGNAL INDICATORS
These lamps are used to indicate to the operator
which turn signal is ON. Power for the lamps comes
from the turn signal switch. The L60 circuit is for the
right turn indicator, and the L61 circuit is used for
the left turn signal indicator. Ground for the circuits
is provided on the Z3 circuit.
BRAKE WARNING INDICATOR LAMP
The Brake Warning Indicator lamp is used to alert
the operator of a problem with the vehicles braking
system. The lamp illuminates when the ignition
switch is turned to START position to perform a self
check.
8W - 40 - 8 8W - 40 INSTRUMENT CLUSTERPL
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine There are two switches used in this system and
they are wired in parallel form. A parking brake
switch located on the parking brake mechanism will
illuminate the lamp if the normally OPEN switch is
CLOSED. This switch is case grounded.
The other switch used is the brake warning lamp
switch. This switch is normally OPEN. When the
brake system pressure is below a predetermined level
the switch CLOSES and completes a path to ground
from the G9 circuit at the cluster, through the
switch, to the left headlamp ground.
ANTI-LOCK WARNING LAMP
The Anti-Lock warning lamp is used to alert the
driver of a problem in the ABS system. When the
ABS controller determines a problem in the system it
grounds the G19 circuit and illuminates the lamp.
HELPFUL INFORMATION
²Check the 5 amp fuse in cavity 11 of the fuse
block.
²Check the 4 amp fuse in cavity 12 of the fuse
block.
²Check the Ignition-Off Draw fuse in the PDC.
²Check for a good ground at the instrument panel
left center support.
²For additional diagnostic tests refer to the
appropriate section of the Service Manual.
PL8W - 40 INSTRUMENT CLUSTER 8W - 40 - 9
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine 8W-43 AIRBAG SYSTEM
DESCRIPTION AND OPERATION
AIRBAG CONTROL MODULE (ACM)
Two different circuits supply battery voltage from
the fuse block to the Airbag Control Module (ACM),
F15 and F25. The F15 and F25 circuits are connected
to separate bus bars internal to the fuse block. Dif-
ferent circuits from the Power Distribution Center
(PDC) and ignition switch supply battery voltage to
the fuse block bus bars.
The F25 circuit supplies battery voltage to the
ACM only when the ignition switch is in the RUN
position. The F15 circuit powers the ACM when the
ignition switch is in either the START or RUN posi-
tion.
An internal bus bar in the ignition switch connects
the A1 circuit from the PDC to the A21 circuit when
the switch is either the START or RUN position. The
A21 circuit supplies battery voltage to the bus bar in
the fuse block that feeds the F15 circuit. A 30 amp
fuse in the PDC protects the A1 and A21 circuits. A
10 amp fuse in the fuse block, cavity 9, protects the
F15 circuit.
When the ignition switch is in the RUN position, it
connects the A2 circuit from the PDC to the A22 cir-
cuit. The A22 circuit supplies battery voltage to the
fuse block bus bar that feeds the F25 circuit. A 40
amp fuse in the PDC protects the A2 and A22 cir-
cuits. A 10 amp fuse in the fuse block, cavity 5, pro-
tects the F25 circuit.
Circuits D1 and D2 are connected to the CCD Bus
and the ACM. The CCD bus is used to provide com-
munications between modules and the universal data
link connector.
The ACM has a case ground and an external dedi-
cated ground, circuit Z6. The dedicated ground con-
nects to the instrument panel right center support.
AIRBAG IMPACT SENSOR
The Airbag system uses a sensor internal to the
Airbag Control Module (ACM) to detect impact. For
information regarding operation of this sensor, refer
to the appropriate group of the Service Manual.
AIRBAG SQUIB (AIRBAG IGNITER)
DRIVERS SIDE AIRBAG
Two circuits, R43 and R45, connect the ACM to the
drivers side airbag module squib (igniter) after pass-
ing through the clock spring connector. Circuit R43
from cavity 3 of the ACM 4-way connector connects
to the squib. Circuit R45 from cavity 4 of the ACM
4-way connector connects to the squib. R43 and R45
are a twisted pair of wires.
PASSENGERS SIDE AIRBAG
Two circuits, R42 and R44, connect the ACM to the
passengers side airbag module squib (igniter). Circuit
R42 from cavity 1 of the ACM 4-way connector con-
nects to the squib. Circuit R44 from cavity 2 of the
ACM 4- way connector connects to the squib. R42
and R44 are a twisted pair of wires.
Circuits R50 and R51 are connected from the ACM
to the passangers airbag. These circuits are used to
monitor the pressure switch.
AIRBAG WARNING LAMP
The Airbag Warning lamp is used to alert the oper-
ator of a problem with the Airbag system. The lamp
is illuminated when the Airbag Control Module
(ACM) grounds the R41 circuit. Refer to the appro-
priate section of the Service Manual or Diagnostic
Test Procedures Manual to diagnosis this system.
HELPFUL INFORMATION
²Check for blown fuses in the circuit that connect
to the ignition switch and those that connect to the
ACM.
²While the bus bars in the fuse block power the
ACM, they also feed additional components on sepa-
rate fuse protected circuits.
²The ACM has a case ground and an external
dedicated ground. The dedicated ground connects to
the instrument panel right center support.
PL8W - 43 AIRBAG SYSTEM 8W - 43 - 5