2000 DODGE NEON ECU

CAUTION: The radiator pressure tester is very sen-
sitive to small air leaks that will not cause cooling
system problems. A pressure cap that does not
have a history of coolant loss should not be
replaced just because it leaks slowly when tested
with this tool. Add water to the tool. Turn the tool
upside down, and recheck the pressure cap to con-
firm that the cap is faulty.
If the pressure cap tests properly while posi-
tioned the on radiator pressure tester, but will not
hold pressure or vacuum when positioned on the
filler neck, inspect the filler neck and cap top gas-
ket for irregularities that may prevent the cap from
sealing properly.
LOW COOLANT LEVEL AERATION
²Will cause corrosion in the system.
²High reading shown on the temperature gauge.
²Air in the coolant will also cause loss of flow
through the heater.
²Exhaust gas leaks into the coolant can also
cause the above problems.
DEAERATION
Air can only be removed from the system by gath-
ering under the pressure cap. On the next heat up it
will be pushed past the pressure cap into the coolant
recovery container by thermal expansion of the cool-
ant. It then escapes to the atmosphere in the coolant
recovery container and is replaced with coolant on
cool down.
TEMPERATURE GAUGE INDICATION
At idle the temperature gauge could rise slowly to
about 1/2 gauge travel. The fan will come on and the
gauge could drop to about 1/3 gauge travel, this is
normal.
ENGINE BLOCK HEATER
If heater unit does not operate (Fig. 15), possible
causes can be either the power cord or the heater ele-
ment. Test the power cord for continuity with a 110-
volt voltmeter or 110-volt test light. Test heater
element continuity with an ohmmeter or a 12-volt
test light.
CAUTION: To prevent damage, the power cord
must be secured in its retainer clips and away from
any components that may cause abrasion or dam-
age, such as linkages, exhaust components, etc.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
NOTE: Do not remove radiator cap for routine cool-
ant level inspections.
The coolant recovery/reserve system provides a
quick visual method for determining the coolant level
without removing the radiator cap. Simply observe,
with the engine idling and warmed up to normal
operating temperature, that the level of the coolant
in the recovery/reserve container (Fig. 16) is between
the FULL HOT and ADD marks.
Fig. 14 Pressure Testing Radiator Cap
1 ± PRESSURE CAP
2 ± PRESSURE TESTER
Fig. 15 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
PLCOOLING SYSTEM 7 - 17
DIAGNOSIS AND TESTING (Continued)

(2) Connect recovery hose to water outlet connec-
tor/thermostat housing (Fig. 29).
(3) Fill container to proper level. Refer to Cooling
System Refilling in this section.
ENGINE BLOCK HEATER
REMOVAL
(1) Drain coolant from radiator and cylinder block.
Refer to Cooling System Draining in this section for
procedure.
(2) Detach power cord plug from heater (Fig. 31).
(3) Loosen screw in center of heater. Remove
heater assembly (Fig. 31).
INSTALLATION
(1) Thoroughly clean core hole and heater seat.
(2) Insert heater assembly with element loop posi-
tionedupward (Fig. 31).
(3) With heater seated, tighten center screw
securely to assure a positive seal.
(4) Connect power cord to block heater (Fig. 31).
(5) Fill cooling system with coolant to the proper
level, vent air, and inspect for leaks.
ACCESSORY DRIVE BELTS
POWER STEERING PUMP AND AIR CONDITIONING
COMPRESSOR BELT
REMOVAL
(1) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be removed from
power steering pump pulley. Gently, release spring
tension on tensioner.
(2) Remove belt (Fig. 34).
INSTALLATION
(1) Install belt (Fig. 34) over all pulleys except for
the power steering pump pulley.
(2) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be installed onto
power steering pulley. Release spring tension onto
belt.
NOTE: When installing drive belt onto pulleys,
make sure that belt is properly routed and all
V-grooves make proper contact with pulley grooves.
(3) After belt is installed, inspect belt length indi-
cator marks (Fig. 35). The indicator mark should be
within the minimum belt length and maximum belt
length marks. On a new belt, the indicator mark
should align approximately with the nominal belt
length mark.
Fig. 31 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
Fig. 32 Accessory Drive Belts
1 ± GENERATOR BELT
2 ± AUTOMATIC BELT TENSIONER
3 ± POWER STEERING PUMP/A/C COMPRESSOR BELT
7 - 24 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

REMOVAL AND INSTALLATION
BATTERY
REMOVAL
WARNING: TO PROTECT THE HANDS FROM BAT-
TERY ACID, A SUITABLE PAIR OF HEAVY DUTY RUB-
BER GLOVES, NOT THE HOUSEHOLD TYPE, SHOULD
BE WORN WHEN REMOVING OR SERVICING A BAT-
TERY. SAFETY GLASSES ALSO SHOULD BE WORN.
(1) Make sure ignition switch is in OFF position
and all accessories are OFF.
(2) Open hood.
(3) Disconnect and isolate the battery negative
cable then the positive cable (Fig. 16).
(4) Remove thermowrap from battery.
(5) Loosen bolt and retainer that holds the battery
down to the tray.
(6) Lift battery out of battery tray and remove
from vehicle.
INSTALLATION
When replacing battery, the Thermowrap MUST be
transferred to the new battery. Refer to Battery Ther-
mowrap Removal and Installation in this section.
(1) Install battery in vehicle making sure that the
thermowrap is present and battery is properly posi-
tioned on battery tray.(2) Install battery hold down clamp, making sure
that it is properly positioned on battery.
(3)
Connect battery cable clamps to battery posts and
making sure top of clamp is flush or below with top of
post (Fig. 16). Install battery positive cable first.
(4) Tighten clamp nuts securely.
BATTERY THERMOWRAP
REMOVAL
(1) Open hood.
(2) Disconnect and isolate the battery negative
cable then the positive cable (Fig. 16).
(3) Carefully lift the thermowrap off over the bat-
tery (Fig. 17) taking care not to rip it.
Fig. 16 Disconnect and Isolate the
Battery Negative Cable
1 ± NEGATIVE CABLE
2 ± NEGATIVE BATTERY POST
Fig. 17 Battery Thermowrap
1 ± BATTERY THERMOWRAP
2 ± BATTERY
8A - 10 BATTERYPL

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

To diagnose the cluster lamps first place the clus-
ter in self-diagnostic mode. With the ignition switch
in the off position, press the trip odometer reset but-
ton down. Simultaneously turn the ignition key to
the ON position and release the trip reset button. All
the indicator lamps and VF displays should illumi-
nate except for the fog lamp, turn signal, and high
beam select indicators. Refer to (Fig. 2), (Fig. 3), and
the Cluster Identification table.
1 ± FOG LAMP
2 ± BRAKE**
3 ± TRAC OFF**
4 ± ABS**
5 ± SPEEDOMETER
6 ± LEFT/RIGHT TURN SIGNAL
7 ± HIGH BEAM
8 ± TACHOMETER
9 ± OIL PRESSURE**
10 ± SEAT BELT**
11 ± BATTERY**
12 ± AIR BAG**
13 ± SECURITY*
14 ± FUEL FILLER DOOR LOCATOR
15 ± FUEL GAUGE
16 ± LOW FUEL*
17 ± MALFUNCTION INDICATOR LAMP (MIL)**
18 ± TRIP RESET BUTTON
19 ± TRAC**
20 ± ODOMETER**
21 ± DOOR (AJAR)**
22 ± SET CRUISE*
23 ± TRIP**
24 ± CRUISE*
25 ± TEMPERATURE GAUGE
*ILLUMINATE DURING SELF-DIAGNOSTICS
**ILLUMINATE DURING BULB CHECK AND SELF-DIAGNOSTICS
LOW OIL PRESSURE WARNING LAMP TEST
The low oil pressure warning lamp will illuminate
when the ignition switch is turned to the ON position
without engine running. The lamp also illuminates if
the engine oil pressure drops below a safe oil pres-
sure level.To test the system, turn the ignition switch to the
ON position. If the lamp fails to light, inspect for a
broken or disconnected wire at the oil pressure
switch, located at the front of the engine (Fig. 4). If
the wire at the connector checks good, pull the con-
nector loose from the switch and with a jumper wire,
ground the connector to the engine. With the ignition
switch turned to the ON position, check the warning
lamp. If the lamp still fails to light, inspect for a
burned out lamp or disconnected socket in the clus-
ter.
Fig. 2 Base Instrument Cluster Without Tachometer
Fig. 3 Premium Instrument Cluster With Tachometer
1 ± FOG LAMP
2 ± BRAKE**
3 ± TRAC OFF**
4 ± ABS**
5 ± SPEEDOMETER
6 ± LEFT/RIGHT TURN SIGNAL
7 ± HIGH BEAM
8 ± TACHOMETER
9 ± OIL PRESSURE**
10 ± SEAT BELT**
11 ± BATTERY**
12 ± AIR BAG**
13 ± SECURITY*
14 ± FUEL FILLER DOOR LOCATOR
15 ± FUEL GAUGE
16 ± LOW FUEL*
17 ± MALFUNCTION INDICATOR LAMP (MIL)**
18 ± TRIP RESET BUTTON
19 ± TRAC**
20 ± ODOMETER**
21 ± DOOR (AJAR)**
22 ± SET CRUISE*
23 ± TRIP**
24 ± CRUISE*
25 ± TEMPERATURE GAUGE
*ILLUMINATE DURING SELF-DIAGNOSTICS
**ILLUMINATE DURING BULB CHECK AND SELF-DIAGNOSTICS
PLINSTRUMENT PANEL SYSTEMS 8E - 3
DIAGNOSIS AND TESTING (Continued)

(10) Connect the (3) wire harnesses on the top of
the I. P.
(11) Connect the I. P. wire harness and secure in
place by attaching the connectors to the steering col-
umn casting with (2) retaining screws. Clip the har-ness retainer at the bottom of the holder and secure
with (2) retainer clips.
(12) Clip the Data Link Connector on the right
side of the I. P. frame.
(13) Install the HVAC control head retaining
screws.
(14) Install the center instrument bezel.
(15) Install the (2) screws in the center instrument
bezel (Fig. 20).
(16) Install the (4) HVAC control knobs.
Fig. 17 Left I. P. Retaining Bolts
1 ± A-PILLAR TRIM
2 ± INSTRUMENT PANEL RETAINING BOLTS
Fig. 18 Right I. P. Retaining Bolts
1 ± INSTRUMENT PANEL RETAINING BOLTS
Fig. 19 Center I. P Retaining Bolts
1 ± INSTRUMENT PANEL CENTER RETAINING BOLTS
Fig. 20 Center Instrument Bezel Retaining Screws
1 ± CENTER BEZEL
2±
CENTER BEZEL RETAINING SCREWS (BEHIND REGISTERS)
PLINSTRUMENT PANEL AND SYSTEMS 8E - 7
REMOVAL AND INSTALLATION (Continued)

AUDIO SYSTEM
TABLE OF CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION..........................1
DESCRIPTION AND OPERATION
INTERFERENCE ELIMINATION...............1
DIAGNOSIS AND TESTING
AUDIO DIAGNOSTIC TEST PROCEDURES......1
TESTING................................1
BENCH TEST FOR ANTENNA MALFUNCTION...7REMOVAL AND INSTALLATION
CD CHANGER............................7
FRONT DOOR SPEAKER....................8
INSTRUMENT PANEL SPEAKER(S)...........8
MAST and ANTENNA ASSEMBLY.............8
RADIO..................................9
REAR SHELF SPEAKER(S).................10
GENERAL INFORMATION
INTRODUCTION
Operating instructions for the factory installed
audio systems can be found in the Owner's Manual
provided with the vehicle.
The vehicles are equipped with an Interior (Igni-
tion Off Draw) fuse in the Power Distribution Center
located in the engine compartment. After the Interior
(IOD) fuse or battery has been disconnected the clock
will require resetting. The radio station presets have
a nonvolatile memory and will retain the preset sta-
tions after a battery disconnect.
The available radio options are:
²AM/FM Stereo Cassette w/Clock
²AM/FM/CD
²AM/FM Cassette w/CD Changer Controls and
Display
²CD/4 Disc Changer - In-Dash (used w/Radio CD
Changer Controls)
DESCRIPTION AND OPERATION
INTERFERENCE ELIMINATION
The radio utilizes a ground wire plugged on to a
blade terminal and is bolted to the radio chassis.
Both connector and terminal should be securely
attached. The engine has two separate ground straps
to suppress ignition noise which may interfere with
radio reception.
²Left engine mount clip on strap
²Engine to shock tower reinforcement
Inductive type spark plug cables in the high ten-
sion circuit of the ignition system complete the inter-
ference suppression. Faulty or deteriorated spark
plug wires should be replaced.
DIAGNOSIS AND TESTING
AUDIO DIAGNOSTIC TEST PROCEDURES
CAUTION: The CD player will only operate between
approximate temperatures of -23ÉC and +65ÉC (-10ÉF
and +145ÉF).
Whenever a radio malfunction occurs;
(1) First check FUSES:
(a) Power Distribution Center (PDC), Interior
lamp fuse, M1 - Radio Memory Feed
(b) Fuse Block:
(I) Fuse 12, Illumination in the fuse block
(II) Fuse 16, Ignition feed in the fuse block
NOTE: The vehicles are shipped with the INTERIOR
LAMP fuse disconnected.
(2) Verify, the radio wire harness are properly con-
nected before starting normal diagnosis and repair
procedures. Refer to Audio Diagnostic Charts and/or
Group 8W, Wiring Diagrams, Radio Section.
TESTING
The antenna has a short cable which connects into
the instrument panel harness. The connection is
made on the right side of the instrument panel.
Antenna performance may be tested by substitut-
ing a known good antenna. It is also possible to
check short or open circuits with an ohmmeter or
continuity light once the antenna cable is discon-
nected from the radio as follows:
(1) Continuity should be present between the
antenna mast and radio end pin of antenna cable
plug (Fig. 1).
(2) No continuity should be observed or a very
high resistance of several megohms between the
ground shell of the connector and radio end pin.
PLAUDIO SYSTEM 8F - 1

CONDITION POSSIBLE CAUSES CORRECTION
HEADLAMPS ARE DIM
WITH ENGINE IDLING OR
IGNITION TURNED OFF1. Loose or corroded battery cables. 1. Clean and secure battery cable clamps
and posts.
2. Loose or worn generator drive
belt.2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system, refer to
Group 8A,
4. Battery has insufficient charge. 4. Test battery state-of-charge,
refer to Group 8A.
5. Battery is sulfated or shorted. 5. Load test battery, refer to Group 8A.
6. Poor lighting circuit Z1 - ground. 6. Test for voltage drop across Z1 - ground
locations, refer to Group 8W.
7. Both headlamp bulbs defective. 7. Replace both headlamp bulbs.
HEADLAMP BULBS BURN
OUT FREQUENTLY1. Charging system output too high. 1. Test and repair charging system, refer to
Group 8A.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and
splices, refer to Group 8W.
HEADLAMPS ARE DIM
WITH ENGINE RUNNING
ABOVE IDLE*1. Charging system output too low. 1. Test and repair charging system, refer to
Group 8A.
2. Poor lighting circuit Z1 - ground. 2. Test for voltage drop across Z1 - ground
locations, refer to Group 8W.
3. High resistance in headlamp
circuit.3. Test amperage draw of headlamp circuit.
4. Both headlamp bulbs defective. 4. Replace both headlamp bulbs.
HEADLAMPS FLASH
RANDOMLY1. Poor lighting circuit Z1 - ground. 1. Test for voltage drop across Z1 - ground
locations, refer to Group 8W.
2. High resistance in headlamp
circuit.2. Test amperage draw of headlamp circuit.
Should not exceed 30 amps.
3. Faulty headlamps switch circuit
breaker.3. Replace headlamp switch.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors and
splices, refer to Group 8W.
HEADLAMPS DO NOT
ILLUMINATE1. No voltage to headlamps. 1. Repair open headlamp circuit, refer to
Group 8W.
2. No Z1 - ground at headlamps. 2. Repair circuit ground, refer to Group 8W.
3. Faulty headlamp switch. 3. Replace headlamp switch.
4. Faulty headlamp dimmer
(multi-function) switch.4. Replace multi-function switch.
5. Broken connector terminal or wire
splice in headlamp circuit.5. Repair connector terminal or wire splice.
Headlamps stay on with key
out (DRL equipped
vehicles).1. Failed DRL function in cluster 1. Replace cluster.
Turn signals do not come
ON.1. Wrong cluster installed. 1. Replace cluster.
2. Bit not set. 2. Set bit.
*Canada vehicles must have lamps ON.
8L - 2 LAMPSPL
DIAGNOSIS AND TESTING (Continued)