light DODGE NEON 1999 Service Owner's Guide

SERVICE DIAGNOSIS±CLUTCH PEDAL NOISE
CONDITION POSSIBLE CAUSES CORRECTION
CLUTCH PEDAL SQUEAKS
WHEN DEPRESSED TO FLOORPedal bushings worn out or
inadequate lubricationReplace or lubricate bushings
CLASH±INTO±REVERSE COMPLAINTS
Some Right Hand Drive NV T350 (A-578) manual
transaxles are equipped with a reverse brake. It pre-
vents clash when shifting into reverse, but only if the
vehicle is not moving. See Group 21, Transaxle for
further diagnosis.
(1) Depress clutch pedal to floor and hold. After
three seconds, shift to reverse. If clash is present,
clutch has excessive spin time, and the reverse brake
may not be functioning.
NOTE: Verify that nothing is obstructing pedal
travel. Floormats or other articles located under-
neath the clutch pedal could prevent the clutch
from disengaging fully. Also make sure that the
hydraulic clutch release mechanism is functioning
properly.
(2) Remove transaxle. See Group 21, Manual Tran-
saxle for procedure.
(3) Check the input shaft spline, clutch disc
splines, and release bearing for dry rust. If present,
clean rust off and apply a light coat of bearing grease
to the input shaft splines. Apply grease on the input
shaft splines only where the clutch disc slides. Verify
that the clutch disc slides freely along the input shaft
spline.
(4) Check to see if the clutch disc hub splines are
damaged, and replace with new clutch assembly if
required.
(5) Check the input shaft for damaged splines.
Replace as necessary.
(6) Check for broken clutch cover diaphragm
spring fingers.
(7) Install clutch assembly and transaxle.
REMOVAL AND INSTALLATION
CLUTCH MASTER CYLINDER Ð RIGHT HAND
DRIVE (RHD)
The clutch master cylinder and remote reservoir
are serviced as an assembly. The linkage components
and cylinder cannot be overhauled or serviced sepa-
rately.
REMOVAL
(1) Hoist vehicle.
(2) Disconnect quick-connector coupler at lower
hydraulic damper using Special Tool 6638 (Fig. 3).(3) Lower vehicle.
(4) Unsnap hydraulic line from left rail retainer
clips (Fig. 4).
(5) From underneath dash panel, remove cotter
pin from pedal bushing.
(6) Remove pedal pivot pin from master pushrod
assembly and bushing.
NOTE: Verify that the reservoir cap is on securely.
This is necessary to avoid undue spillage during
removal.
(7) Slide remote reservoir up out of bracket.
Fig. 3 Quick-Connect Coupler
Fig. 4 Routing Clips
6 - 6 CLUTCHPL
DIAGNOSIS AND TESTING (Continued)

SELECTION AND ADDITIVES
The use of aluminum cylinder heads, intake mani-
folds DOHC, and water pumps requires special corro-
sion protection. MopartAntifreeze or the equivalent
is recommended for best engine cooling without cor-
rosion. When mixed only to a freeze point of -37ÉC
(-35ÉF) to -59ÉC (-50ÉF). If it looses color or becomes
contaminated, drain, flush, and replace with fresh
properly mixed solution.
COOLING SYSTEM PRESSURE CAP
The cooling system is equipped with a pressure cap
that releases built up pressure, maintaining a range
of 97-124 kPa (14-18 psi).
The cooling system will operate at higher than
atmospheric pressure. The higher pressure raises the
coolant boiling point thus, allowing increased radia-
tor cooling capacity.
There is a vent valve in the center of the cap that
allows a small coolant flow from the coolant reserve
system (CRS) tank. This valve is spring loaded in the
closed position. However it must be free to open dur-
ing system cool-down.If the valve is stuck shut,
the radiator hoses will collapse on cool-down.
Clean the vent valve (Fig. 7) to ensure proper
sealing function.
There is a gasket in the cap that seals to the top of
the filler neck so that vacuum is maintained to draw
coolant back into the system from the coolant reserve
system (CRS) tank.
RADIATOR HOSES AND CLAMPS
WARNING: IF VEHICLE HAS BEEN RUN
RECENTLY, WAIT 15 MINUTES BEFORE WORKING
ON VEHICLE. RELIEVE PRESSURE BY PLACING A
SHOP TOWEL OVER THE CAP AND WITHOUT
PUSHING DOWN ROTATE IT COUNTERCLOCKWISE
TO THE FIRST STOP. ALLOW FLUIDS TO ESCAPE
THROUGH THE OVERFLOW TUBE AND WHEN THE
SYSTEM STOPS PUSHING OUT COOLANT AND
STEAM AND THE PRESSURE DROPS CONTINUE
SERVICE.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAM. ALWAYS WEAR SAFETY GLASSES WHEN
SERVICING CONSTANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only a original equipment clamp
with matching number or letter.The hose clamps are removed by using Special Tool
6094 or equivalent constant tension clamp pliers
(Fig. 8) to compress hose clamp.
A hardened, cracked, swollen or restricted hose
should be replaced. Do not damage radiator inlet and
outlet when loosening hoses.
Radiator hoses should be routed without any kinks
and indexed as designed. The use of molded hoses is
recommended.
Spring type hose clamps are used in all applica-
tions. If replacement is necessary replace with the
original Mopartequipment spring type clamp.
ENGINE BLOCK HEATER
The heater is mounted in a core hole (in place of a
core hole plug) in the engine block, with the heating
element immersed in coolant.The power cord
must be secured in its retainer clips, and not
positioned so it could contact linkages or
exhaust manifolds and become damaged.
If unit does not operate, trouble can be in either
the power cord or the heater element. Test power
cord for continuity with a 110-volt voltmeter or 110-
volt test light; test heater element continuity with an
ohmmeter or 12-volt test light.
Fig. 7 Cooling System Pressure Cap
PLCOOLING 7 - 5
DESCRIPTION AND OPERATION (Continued)

ENGINE THERMOSTAT TESTING
The thermostat is operated by a wax filled con-
tainer (pellet) which is sealed. When heated coolant
reaches a predetermined temperature the wax pellet
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
Coolant leakage into the pellet will cause a thermo-
stat to fail open. Do not attempt to free up a thermo-
stat with a screwdriver.The thermostat that opens too soon type failure
mode is included in the on-board diagnosis. The
check engine light will not be lit by an open too soon
condition. If it has failed open, a diagnostic trouble
code (DTC) will be set. Do not change a thermostat
for lack of heater performance or temperature gauge
position, unless a DTC is present. See Diagnosis for
other probable causes. Thermostat failing shut is the
normal long term mode of failure, and normally, only
on high mileage vehicles. The temperature gauge will
indicate this. Refer to Diagnosis in this section.
ACCESSORY DRIVE BELT DIAGNOSIS
CONDITION POSSIBLE CAUSE CORRECTION
INSUFFICIENT ACCESSORY
OUTPUT DUE TO BELT SLIPPAGE1. Belt too loose. 1. Adjust belt tension.
2. Belt excessively glazed or worn. 2. Replace and tighten as specified.
BELT SQUEAL WHEN
ACCELERATING ENGINE1. Belts too loose. 1. Adjust belt tension.
2. Belts glazed. 2. Replace belts.
BELT CHIRP AT IDLE 1. Belts too loose. 1. Adjust belt tension.
2. Foreign material imbedded in
belt.2. Replace belt.
3. Non-uniform belt. 3. Replace belt.
4. Misaligned pulley(s). 4. Align accessories.
5. Non-uniform groove or eccentric
pulley.5. Replace pulley(s).
BELT ROLLED OVER IN GROOVE
OR BELT JUMPS OFF1. Broken cord in belt. 1. Replace belt.
2. Belt too loose, or too tight. 2. Adjust belt tension.
3. Misaligned pulleys. 3. Align accessories.
4. Non-uniform grooves or eccentric
pulley.4. Replace pulley(s).
PLCOOLING 7 - 13
DIAGNOSIS AND TESTING (Continued)

escapes to the atmosphere in the CRS tank and is
replaced with solid 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.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
NOTE: Do not remove radiator cap for routine cool-
ant level inspections.
The coolant 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
reserve tank (Fig. 12) is between the add and full
marks.
COOLANTÐADDING ADDITIONAL
NOTE: The radiator cap should not be removed.
When additional coolant is needed, it should be
added to the coolant reserve tank. Use only 50/50
concentration of ethylene glycol type antifreeze and
water
COOLANT LEVELÐSERVICING
NOTE: The cooling system is closed and designed
to maintain coolant level to the top of the radiator.When servicing requires a coolant level check in
the radiator, the engine must beoffandnotunder
pressure. Drain several ounces of coolant from the
radiator drain cock while observing the Coolant
Recovery System (CRS) Tank. Coolant level in the
CRS tank should drop slightly. Then remove the radi-
ator cap. The radiator should be full to the top. If
not, and the coolant level in the CRS tank is at the
ADD mark there is a air leak in the CRS system.
Check hose or hose connections to the CRS tank,
radiator filler neck or the pressure cap seal to the
radiator filler neck for leaks.
COOLING SYSTEMÐDRAINING
NOTE: Drain, flush, and fill the cooling system at
the mileage or time intervals specified in Group 0,
Lubrication and Maintenance. If the solution is dirty,
rusty, or contains a considerable amount of sedi-
ment; clean and flush with a reliable cooling system
cleaner. Care should be taken in disposing of the
used engine coolant from your vehicle. Check gov-
ernmental regulations for disposal of used engine
coolant.
Without removing radiator pressure cap and
with system not under pressure:
(1) Shut engine off and turn draincock counter-
clockwise to open (Fig. 13).
(2) The coolant reserve tank should empty first,
then remove the pressure cap. (if not, Refer to Test-
ing Cooling System for leaks).
Fig. 11 Pressure Testing Radiator Cap
Fig. 12 Coolant Recovery System
7 - 16 COOLINGPL
DIAGNOSIS AND TESTING (Continued)

(5) Impeller loose or damaged.
(6) Sprocket or sprocket flange loose or damaged.
ACCESSORY DRIVE BELT INSPECTION
Belt replacement under any or all of the following
conditions is required, excessive wear, frayed cords or
severe glazing.
Poly-V-Belt system may develop minor cracks
across the ribbed side. These minor cracks are con-
sidered normal and acceptable. Cracks parallel are
not (Fig. 28).
NOTE: Do not use any type of belt dressing or
restorer on Poly-V-Belts.
COOLING SYSTEM CAP
Hold the cap in your hand,right side up(Fig. 29).
The vent valve at the bottom of the cap should open
with a slight pull. If the rubber gasket has swollen,
preventing the valve from opening, replace the cap.
If any light can be seen between vent valve and
the rubber gasket, replace the cap.Use only a
replacement cap that has a spring to hold the
vent shut.
A replacement cap must be of the type designed for
coolant reserve systems. This design ensures system
pressurization.
CLEANING COOLING SYSTEM
Drain cooling system (see:Draining Cooling Sys-
tem) and refill with clean water (see:Refilling
Fig. 26 Power Steering Pump Adjustment
BELT TENSION CHART
ACCESSORY
DRIVE BELTGAUGE TORQUE
Power Steering
Pump and A/C
CompressorNew 135 lb. 121 N´m (90 ft.
lbs.)
Used 100 lb. 81 N´m 60 ft.
lbs.)
Generator New 135 lb. Gauge
adjustment
method only Used 100 lb.
Fig. 27 Generator Adjustment
Fig. 28 Drive Belt Wear Pattern
7 - 22 COOLINGPL
CLEANING AND INSPECTION (Continued)

NOTE: BLACK OR DARK=0to75%state-of-charge
The battery is INADEQUATELY charged and must
be charged until green dot is visible, (12.4 volts or
greater) before the battery is tested or returned to
use. Refer to Causes of Battery Discharging in this
Group for more information.
NOTE: CLEAR COLOR = Replace Battery
WARNING: DO NOT CHARGE, ASSIST BOOST,
LOAD TEST, OR ADD WATER TO THE BATTERY
WHEN CLEAR COLOR DOT IS VISIBLE. PERSONAL
INJURY MAY OCCUR.
A clear color dot shows electrolyte level in battery
is below the test indicator (Fig. 1). Water cannot be
added to a maintenance free battery. The battery
must be replaced. A low electrolyte level may be
caused by an over charging condition. Refer to Gen-
erator Test Procedures on Vehicle.
CAUSES OF BATTERY DISCHARGING
It is normal to have a small 5 to 25 milliamperes
continuous electrical draw from the battery. This
draw will take place with the ignition in the OFF
position, and the courtesy, dome, storage compart-
ments, and engine compartment lights OFF. The con-
tinuous draw is due to various electronic features or
accessories that require electrical current with the
ignition OFF to function properly. When a vehicle is
not used over an extended period of approximately 20
days the IOD fuse should be pulled. The fuse is
located in the power distribution center. removal of
this fuse will reduce the level of battery discharge.
Refer to the Battery Diagnosis and Testing Table for
proper diagnosis.
ABNORMAL BATTERY DISCHARGING
²Corroded battery posts, cables or terminals.
²Loose or worn generator drive belt.
²Electrical loads that exceed the output of the
charging system due to equipment or accessories
installed after delivery.
²Slow driving speeds in heavy traffic conditions
or prolonged idling with high-amperage electrical
systems in use.
²Defective electrical circuit or component causing
excess Ignition Off Draw (IOD). Refer to Battery
Ignition Off Draw (IOD).
²Defective charging system.
²Defective battery.
BATTERY IGNITION OFF DRAW (IOD)
High current draw on the battery with the ignition
OFF will discharge a battery. After a dead battery is
recharged, the vehicle ignition off draw (IOD) shouldbe checked. To determine if a high current draw con-
dition exists first check the vehicle with a test lamp.
(1) Verify that all electrical accessories are OFF.
²Remove key from ignition switch
²Turn off all lights
²Trunk lid is closed
²Engine compartment hood lamp is disconnected
or lamp removed
²Glove box door is closed
²Sun visor vanity lights are OFF
²All doors are closed
²Allow the ignition key lamp system to time out
in approximately 30 seconds, if equipped.
(2) Disconnect battery negative cable (Fig. 4).
(3) Connect a 12 Volt test lamp, with a cold resis-
tance of 5-7 ohms, between the battery negative cable
clamp and the negative post (Fig. 5). If test lamp
goes out system is OK. If test lamp lights and stays
ON, go to Test Lamp Stays ON procedure.
TEST LAMP STAYS ON
There is either a short circuit or a fault in an elec-
tronic module. Two fuses in the Power Distribution
Center (PDC) feed the modules with ignition off
draw.
²Interior lamps fuse (10 Amp) (IOD) PDC.
²Fuel pump fuse (20 Amp) in PDC
(1) Remove interior lamp and fuel pump fuses. By
removing these fuses all ignition off draw from the
vehicle electronics will be disconnected. The test
lamp should go out. If test lamp goes out go to Step
2. If test lamp does not go out there is a current
draw or short circuit. Refer to Group 8W, Wiring Dia-
grams.
(2) Install the fuel pump fuse. If test lamp lights,
there is a current draw or short circuit in the A14
wiring circuit feed.
(a) Disconnect Powertrain Control Module.
(b) If test lamp goes out, replace Powertrain
Control Module.
(c) If test lamp does not go out, there is a cur-
rent draw or short circuit in the A14 circuit feed.
Refer to Group 8W, Wiring Diagrams.
(3) Install the interior lamp fuse. If test lamp
lights, there is a current draw or short circuit in the
M01 circuit. Refer to Group 8W, Wiring Diagrams. If
test lamp stays out, go to Step 4
(4) Use a multi-meter that has at least a range of
200 milliamperes. Install meter between the battery
negative cable and battery negative post (Fig. 6).
Carefully remove the test lamp without disconnecting
the meter. After all modules time-out the total vehi-
cle IOD should be less than 10 milliamperes. If igni-
tion off draw is more than 10 milliamperes go to Step
5.
(5) Remove both fuses from the Power Distribution
Center:
PLBATTERY 8A - 3
DIAGNOSIS AND TESTING (Continued)

exposure over the preceding several hours. If the bat-
tery has been charged or boosted a few minutes prior
to the test, the battery would be slightly warmer.
Refer to Battery Load Test Temperatures Table for
proper voltage/temperature reading:
(6) If battery passes load test, it is in good condi-
tion and further tests are not necessary. If it fails
load test, it should be replaced.
BATTERY OPEN CIRCUIT VOLTAGE TEST
An open circuit voltage no load test shows the
state of charge of a battery and whether it is ready
for a load test at 50 percent of the battery's cold
crank rating. Refer to Battery Load Test. If a battery
has open circuit voltage reading of 12.4 volts or
greater, and will not pass the load test, replace the
battery because it is defective. To test open circuit
voltage, perform the following operation.
(1) Remove both battery cables, negative cable
first. Battery top, cables and posts should be clean. If
green dot is not visible in indicator, charge the bat-
tery. Refer to Battery Charging Procedures.
(2) Connect a Volt/Ammeter/Load tester to the bat-
tery posts (Fig. 7). Rotate the load control knob of theCarbon pile rheostat to apply a 300 amp load. Apply
this load for 15 seconds to remove the surface charge
from the battery, and return the control knob to off
(Fig. 8).
(3) Allow the battery to stabilize for 2 minutes,
and then verify the open circuit voltage (Fig. 10).
(4) This voltage reading will approximate the state
of charge of the battery. It will not reveal battery
cranking capacity. Refer to Battery Open Circuit
Voltage Table.
BATTERY TEMPERATURE SENSOR
For Battery Temperature Sensor refer to Group 8C
Generator.
SERVICE PROCEDURES
BATTERY CHARGING
A battery is considered fully charged when it will
meet all the following requirements.
²It has an open circuit voltage charge of at least
12.4 volts.
²It passes the 15 second load test. Refer to Bat-
tery Load Test.
²The built in test indicator dot is GREEN (Fig.
1).
NOTE: The battery cannot be refilled with water, it
must be replaced.
Fig. 9 Load 50% Cold Crank Rating
BATTERY LOAD TEST TEMPERATURES
Minimum
VoltageTemperature
ÉF ÉC
9.6 volts 70É and above 21É and above
9.5 volts 60É 16É
9.4 volts 50É 10É
9.3 volts 40É 4É
9.1 volts 30É -1É
8.9 volts 20É -7É
8.7 volts 10É -12É
8.5 volts 0É -18É
Fig. 10 Testing Open Circuit Voltage
BATTERY OPEN CIRCUIT VOLTAGE
Open Circuit Volts Charge Percentage
11.7 volts or less 0%
12.0 volts 25%
12.2 volts 50%
12.4 volts 75%
12.6 volts or more 100%
8A - 6 BATTERYPL
DIAGNOSIS AND TESTING (Continued)

(1) Connect a volt-ampere tester to the battery ter-
minals (Fig. 7). Refer to the operating instructions
provided with the tester being used.
(2) To disable the ignition and fuel systems, dis-
connect the Automatic Shutdown Relay (ASD). The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location. The 2.5L Diesel Engine, to disable the
engine from starting, disconnect wire connector from
the Fuel Solenoid.
(3) Verify that all lights and accessories are OFF,
and the transmission shift selector is in the PARKposition or with the clutch pedal depressed and SET
parking brake.
CAUTION: Do not overheat the starter motor or
draw the battery voltage below 9.6 volts during
cranking operations.
(4) Rotate and hold the ignition switch in the
START position. Observe the volt-ampere tester (Fig.
6).
²If voltage reads above 9.6 volts, and amperage
draw reads above 280 amps or the Diesel engine
above 450 amps, check for engine seizing or faulty
starter.
²If voltage reads 12.4 volts or greater and amper-
age reads 0 to 10 amps, check for corroded cables
and/or bad connections.
²Voltage below 9.6 volts and amperage draw
above 300 amps or Diesel engine above 500 amps,
the problem is the starter. Replace the starter refer
to starter removal.
(5) After the starting system problems have been
corrected, verify the battery state-of-charge and
Fig. 6 Volt Ampere Tester
Fig. 7 Volt-Ampere Tester Connections
Fig. 4 Test Starter Motor Ground
Fig. 5 Test Battery Positive Cable Resistance
PLSTARTING 8B - 3
DIAGNOSIS AND TESTING (Continued)

performed at each (- ground) connection in this cir-
cuit to locate the excessive resistance.
(7) Testing (+ positive) circuitry:
(a) Touch the positive lead of voltmeter directly
to battery negativePOST.
(b) Touch the negative lead of voltmeter to the
ground terminal stud on the generator case (not
the terminal mounting nut). Voltage should be no
higher than 0.3 volts. If voltage is higher than 0.3
volts, touch test lead to terminal mounting stud
nut and then to the wiring connector. If voltage is
now below 0.3 volts, look for dirty, loose or poor
connection at this point. A voltage drop test may be
performed at each (+ positive) connection in this
circuit to locate the excessive resistance. This test
can also be performed between the generator case
and the engine. If test voltage is higher than 0.3
volts, check for corrosion at generator mounting
points or loose generator mounting.
CURRENT OUTPUT TEST
The current output test will determine if the
charging system can deliver its minimum test cur-
rent (amperage) output. Refer to the Specifications
section at the end of this group for minimum test
current (amperage) requirements.
The first part of this test will determine the com-
bined amperage output of both the generator and the
Electronic Voltage Regulator (EVR) circuitry.
PREPARATION
(1) Determine if any Diagnostic Trouble Codes
(DTC) exist. To determine a DTC, refer to On-Board
Diagnostics in this group. For repair, refer to the
appropriate Powertrain Diagnostic Procedures man-
ual.
(2) Before starting test, make sure battery is in
good condition and is fully-charged. See Group 8A,
Battery for more information.
(3) Check condition of battery cables at battery.
Clean if necessary.
(4) Perform the Voltage Drop Test. This will
ensure clean and tight generator/battery electrical
connections.
(5) Be sure the generator drive belt is properly
tensioned. Refer to Group 7, Cooling System for
information.
(6) A volt/amp tester equipped with both a battery
load control (carbon pile rheostat) and an inductive-
type pickup clamp (ammeter probe) will be used for
this test. Refer to operating instructions supplied
with tester. When using a tester equipped with an
inductive-type clamp, removal of wiring at the gener-
ator will not be necessary.
(7) Start the engine and allow it to reach operating
temperature.
(8) Shut engine off.(9) Turn off all electrical accessories and all vehicle
lighting.
(10) Connect the volt/amp tester leads to the bat-
tery. Be sure the carbon pile rheostat control is in the
OPEN or OFF position before connecting leads. See
Load Test in Group 8A, Battery for more information.
Also refer to the operating instructions supplied with
test equipment.
(11) Connect the inductive clamp (ammeter probe).
Refer to the operating instructions supplied with test
equipment.
(12) If volt/amp tester is not equipped with an
engine tachometer, connect a separate tachometer to
the engine.
TEST
(1) Perform the previous test Preparation.
(2) Fully engage the parking brake.
(3) Start engine.
(4) Bring engine speed to 2500 rpm.
(5) With engine speed held at 2500 rpm, slowly
adjust the rheostat control (load) on the tester to
obtain the highest amperage reading. Do not allow
voltage to drop below 12 volts. Record the reading.
This load test must be performed within 15 sec-
onds to prevent damage to test equipment.On
certain brands of test equipment, this load will be
applied automatically. Refer to the operating manual
supplied with test equipment.
(6) The ammeter reading must meet the Minimum
Test Amps specifications as displayed in the Genera-
tor Ratings chart. This can be found in the Specifica-
tions section at the end of this group. A label stating
a part reference number is attached to the generator
case. On some engines this label may be located on
the bottom of the case. Compare this reference num-
ber to the Generator Ratings chart.
(7) Rotate the load control to the OFF position.
(8) Continue holding engine speed at 2500. If EVR
circuitry is OK, amperage should drop below 15±20
amps. With all electrical accessories and vehicle
lighting off, this could take several minutes of engine
operation. If amperage did not drop, refer to the
appropriate Powertrain Diagnostic Procedures man-
ual for testing.
(9) Remove volt/amp tester.
If minimum amperage could not be met, refer to
the appropriate Powertrain Diagnostic Procedures
manual for testing.
BATTERY TEMPERATURE SENSOR
To perform a complete test of this sensor and its
circuitry, refer to the appropriate Powertrain Diag-
nostic Procedures manual. To test the sensor only,
refer to the following:
(1) The sensor is located under the battery and is
attached to the battery tray (Fig. 5). A two-wire pig-
8C - 8 CHARGING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

the camshaft position sensor (Fig. 8) or (Fig. 9) and
crankshaft position sensor. From the two inputs, the
PCM determines crankshaft position.
The camshaft position sensor attaches to the rear
of the cylinder head (Fig. 10). A target magnet
attaches to the rear of the camshaft and indexes to
the correct position. The target magnet has four dif-
ferent poles arranged in an asymmetrical pattern. As
the target magnet rotates, the camshaft position sen-
sor senses the change in polarity (Fig. 11). The sen-
sor input switches from high (5 volts) to low (0.30
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
underneath.
The camshaft position sensor is mounted to the
rear of the cylinder head. The sensor also acts as a
thrust plate to control camshaft endplay on SOHC
engines.
COMBINATION ENGINE COOLANT TEMPERATURE
SENSOR
The coolant temperature sensor provides an input
voltage to the PCM and a separate input voltage to
the temperature gauge on the instrument panel. The
PCM determines engine coolant temperature from
the coolant temperature sensor. As coolant tempera-
ture varies, the coolant temperature sensor resis-
tance changes resulting in a different input voltage
to the PCM.
When the engine is cold, the PCM will demand
slightly richer air-fuel mixtures and higher idle
speeds until normal operating temperatures are
reached.
Fig. 8 Camshaft Position SensorÐSOHC
Fig. 9 Camshaft Position SensorÐDOHC
Fig. 10 Target Magnet ÐTypical
Fig. 11 Target Magnet Polarity
PLIGNITION SYSTEM 8D - 5
DESCRIPTION AND OPERATION (Continued)