1996 CHRYSLER VOYAGER check oil

IGNITION SWITCH OFF MODE
When the ignition switch is turned to the OFF
position, the following occurs:
²All outputs are turned off.
²No inputs are monitored.
²The PCM shuts down.
DESCRIPTION AND OPERATION
SYSTEM DIAGNOSIS
The PCM can test many of its own input and out-
put circuits. If the PCM senses a fault in a major
system, the PCM stores a Diagnostic Trouble Code
(DTC) in memory.
For DTC information, refer to Group 25, Emission
Control Systems. See On-Board Diagnostics.
CCD BUS
Various controllers and modules exchange informa-
tion through a communications port called the CCD
Bus. The PCM transmits the malfunction indicator
(check engine) lamp On/Off signal, engine RPM and
vehicle load information on the CCD Bus.
POWERTRAIN CONTROL MODULE (PCM)
The PCM is a digital computer containing a micro-
processor (Fig. 1). The PCM receives input signals
from various switches and sensors that are referred
to as PCM Inputs. Based on these inputs, the PCM
adjusts various engine and vehicle operations
through devices that are referred to as PCM Out-
puts.PCM Inputs:
²Air Conditioning Head Pressure
²Battery Voltage
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Engine Coolant Temperature Sensor
²Heated Oxygen Sensors (Upstream and Down-
stream)
²Intake Air Temperature Sensor (2.4L only)
²Knock Sensor (execpt 3.0L)
²Manifold Absolute Pressure (MAP) Sensor
²SCI Receive
²Speed Control System Controls
²Throttle Position Sensor
²Transaxle Park/Neutral Position Switch (auto-
matic transaxle)
²Transmission Control Module
²Vehicle Speed Sensor
PCM Outputs:
²Air Conditioning Clutch Relay
²Automatic Shutdown (ASD) Relay
²Data Link Connector
²Proportional Purge Solenoid
²Electric EGR Transducer
²Fuel Injectors
²Fuel Pump Relay
²Generator Field
²Idle Air Control Motor
²Ignition Coil
²Leak Detection Pump
²Malfunction Indicator (Check Engine) Lamp
²Radiator Fan Control Module
²Speed Control Solenoids
²Tachometer Output
²Torque Converter Clutch Solenoid (3 speed
transmission)
²Transmission Control Module
Based on inputs it receives, the PCM adjusts fuel
injector pulse width, idle speed, ignition spark
advance, ignition coil dwell and canister purge oper-
ation. The PCM regulates the cooling fan, air condi-
tioning and speed control systems. The PCM changes
generator charge rate by adjusting the generator
field.
The PCM adjusts injector pulse width (air/fuel
ratio) based on the following inputs:
²Battery voltage
²Engine coolant temperature
²Exhaust gas content (oxygen sensors)
²Engine speed (crankshaft position sensor)
²Manifold absolute pressure
²Throttle position
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Barometric pressure
Fig. 1 Powertrain Control Module (PCM)
14 - 32 FUEL SYSTEMNS
GENERAL INFORMATION (Continued)

Shutdown (ASD) RelayÐPCM Output in this section
for relay operation.
TORQUE CONVERTER CLUTCH SOLENOIDÐPCM
OUTPUT
Three-speed automatic transaxles use a torque con-
verter clutch solenoid. The PCM controls the engage-
ment of the torque converter clutch through the
solenoid. The torque converter clutch is engaged only
in direct drive mode. Refer to Group 21 for transaxle
information.
MALFUNCTION INDICATOR (CHECK ENGINE)
LAMPÐPCM OUTPUT
The PCM supplies the malfunction indicator (check
engine) lamp on/off signal to the instrument panel
through the CCD Bus. The CCD Bus is a communi-
cations port. Various modules use the CCD Bus to
exchange information.
The Check Engine lamp comes on each time the
ignition key is turned ON and stays on for 3 seconds
as a bulb test.
The Malfunction Indicator Lamp (MIL) stays on
continuously, when the PCM has entered a Limp-In
mode or identified a failed emission component. Dur-
ing Limp-in Mode, the PCM attempts to keep the
system operational. The MIL signals the need for
immediate service. In limp-in mode, the PCM com-
pensates for the failure of certain components that
send incorrect signals. The PCM substitutes for the
incorrect signals with inputs from other sensors.
If the PCM detects active engine misfire severe
enough to cause catalyst damage, it flashes the MIL.
At the same time the PCM also sets a Diagnostic
Trouble Code (DTC).
For signals that can trigger the MIL (Check
Engine Lamp) refer to Group 25, On-Board
Dianostics.
SOLID STATE FAN RELAYÐPCM OUTPUT
The radiator fan runs at a variable speed depend-
ing on coolant temperature and A/C system pressure.
The radiator fan circuit contains a Solid State Fan
Relay (SSFR). Refer to the Group 8W for a circuit
schematic.
A 5 volt signal is supplied to the SSFR. The PCM
provides a pulsed ground for the SSFR. Depending
upon the amount of pulse on time, the SSFR puts out
a proportional voltage to the fan motor at the lower
speed. For instance, if the on time is 30 percent, then
the voltage to the fan motor will be 3.6 volts.
When engine coolant reaches approximately 102ÉC
(215ÉF) the PCM grounds the SSFR relay. If engine
coolant reaches 207ÉC (225ÉF) the PCM grounds the
high speed ground relay and high speed fan relay. If
the fan operates at high speed, the PCM de-energizes
the high speed relay and high speed ground relay
when coolant temperature drops to approximately
101ÉC (214ÉF). When coolant temperature drops to
101ÉC (214ÉF) the fan operates at low speed. The
PCM de-energizes the low speed relay when coolant
temperature drops to approximately 93ÉC (199ÉF).
Also, when the air conditioning pressure switch
closes, the fan operates at high speed. The air condi-
tioning switch closes at 285 psi610 psi. When air
conditioning pressure drops approximately 40 psi, the
pressure switch opens and the fan operates at low
speed.
The SSFR relay is located on the left front inner
frame just behind the radiator (Fig. 42).
SPEED CONTROL SOLENOIDSÐPCM OUTPUT
The speed control vacuum and vent solenoids are
operated by the PCM. When the PCM supplies a
ground to the vacuum and vent solenoids, the speed
control system opens the throttle plate. When the
PCM removes the ground from the vacuum and vent
solenoids, the throttle blade closes. The PCM bal-
Fig. 41 Ignition Coil Ð3.3/3.8L
Fig. 42 Fan Control Module
14 - 46 FUEL SYSTEMNS
DESCRIPTION AND OPERATION (Continued)

ances the two solenoids to maintain the set speed.
Refer to Group 8H for speed control information.
TACHOMETERÐPCM OUTPUT
The PCM supplies engine RPM to the instrument
panel tachometer through the CCD Bus. The CCD
Bus is a communications port. Various modules use
the CCD Bus to exchange information. Refer to
Group 8E for more information.
THROTTLE BODY
On all engine assemblies (2.4, 3.0, and 3.3/3.8L)
the throttle body's are located on the left side of the
intake manifold plenum. The throttle body houses
the throttle position sensor and the idle air control
motor. Air flow through the throttle body is con-
trolled by a cable operated throttle blade located in
the base of the throttle body (Fig. 43) or (Fig. 44) or
(Fig. 45).
DIAGNOSIS AND TESTING
VISUAL INSPECTIONÐ2.4L ENGINE
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:
(1) Check ignition cable routing from the coil pack
to the spark plugs. Verify the cable are routed in the
correct order and are fully seated to the coil and
spark plug.
(2) Check direct ignition system (DIS) coil electri-
cal connection for damage and a complete connection
to the coil pack (Fig. 46).
Fig. 43 Throttle BodyÐ2.4L
Fig. 44 Throttle BodyÐ3.0L
NSFUEL SYSTEM 14 - 47
DESCRIPTION AND OPERATION (Continued)

(3) Verify the camshaft position sensor electrical
connector is connected to the harness and not dam-
aged (Fig. 47).(4) Ensure the engine temperature sensor electri-
cal connector is connected to the sensor and not dam-
aged (Fig. 48).
(5) Verify the quick connect fuel fitting is fully
inserted on the fuel supply tube.
(6) Check the oil pressure sending unit electrical
connection.
(7) Verify the electrical connector at the knock sen-
sor is fully seated and not damaged (Fig. 49).
Fig. 45 Throttle BodyÐ3.3/3.8L
Fig. 46 Ignition Coil Pack Electrical Connection
Fig. 47 Camshaft Position Sensor
14 - 48 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

VISUAL INSPECTIONÐ3.0L ENGINE
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:(1) Check for correct spark plug cable routing.
Ensure that the cables are completely connected to
the spark plugs and distributor.
(2) Check ignition coil electrical connections (Fig.
62).
(3) Verify that the electrical connector is attached
to the Proportional Purge Solenoid (Fig. 63).
(4) Verify that vacuum connection at the duty cycle
Proportional Purge Solenoid valve is secure and not
leaking.
Fig. 60 Power Distribution Center (PDC)
Fig. 61 Power Brake Booster Hose
Fig. 62 Ignition Coil Electrical Connection
Fig. 63 Proportional Purge Solenoid Valve
14 - 52 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

(13) Ensure the harness connector is securely
attached to each fuel injector.
(14) Check the oil pressure sending unit electrical
connection (Fig. 69).
(15) Check hose connections at throttle body.
(16) Check throttle body electrical connections
(Fig. 70).
(17) Check PCV hose connections (Fig. 71).
(18) Check EGR system vacuum hose connections
(Fig. 72).
(19) Check EGR tube to intake plenum connec-
tions.
(20) Check power brake booster vacuum connec-
tions.
(21) Check engine harness to main harness electri-
cal connections.
(22) Check all electronic automatic transaxle elec-
trical connections (Fig. 73).(23) Inspect the Powertrain Control Module (PCM)
40-way electrical connectors for damage or spread
Fig. 69 Oil Pressure Sending Unit Electrical
Connection
Fig. 70 Throttle Body Electrical and Vacuum Hose
Connections
Fig. 71 Positive Crankcase Ventilation (PCV) System
Fig. 72 EGR System
Fig. 73 Electronic Automatic Transaxle Electrical
Connections
14 - 54 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

terminals. Verify the connectors are fully inserted
into the socket of the PCM (Fig. 74). Ensure that
wires are not stretched or pulled out of the connector.
(24) Inspect fuses in the Power Distribution Cen-
ter (PDC). Verify all fuses and relays are fully
inserted into the PDC (Fig. 74). A label affixed to the
underside of the PDC cover identifies the relays and
fuses in the PDC.
(25) Check Battery Cable Connections.
(26) Check hose and wiring connections at fuel
pump module. Check that wiring connector is making
contact with terminals on pump.
VISUAL INSPECTIONÐ3.3/3.8L ENGINES
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:
(1) Check ignition cable routing from the coil pack
to the spark plugs. Verify the cable are routed in the
correct order and are fully seated to the coil and
spark plug.(2) Check direct ignition system (DIS) coil electri-
cal connection for damage and a complete connection
to the coil pack (Fig. 75).
(3) Verify the camshaft position sensor electrical
connector is connected to the harness and not dam-
aged (Fig. 76).
(4) Ensure the engine temperature sensor electri-
cal connector is connected to the sensor and not dam-
aged (Fig. 77).
(5) Verify the quick connect fuel fitting is fully
inserted on the fuel supply tube.
(6) Check the oil pressure sending unit electrical
connection (Fig. 78).
Fig. 74 Powertrain Control Module (PCM)
Fig. 75 Ignition Coil Pack Electrical Connection
Fig. 76 Camshaft Position Sensor
NSFUEL SYSTEM 14 - 55
DIAGNOSIS AND TESTING (Continued)

²The PCM grounds the coil side of the relay
through terminal number 85.
²Terminal number 86 supplies voltage to the coil
side of the relay.
²When the PCM de-energizes the ASD and fuel
pump relays, terminal number 87A connects to termi-
nal 30. This is the Off position. In the off position,
voltage is not supplied to the rest of the circuit. Ter-
minal 87A is the center terminal on the relay.
²When the PCM energizes the ASD and fuel
pump relays, terminal 87 connects to terminal 30.
This is the On position. Terminal 87 supplies voltage
to the rest of the circuit.
TESTING
The following procedure applies to the ASD and
fuel pump relays.
(1) Remove relay from connector before testing.
(2) With the relay removed from the vehicle, use
an ohmmeter to check the resistance between termi-
nals 85 and 86. The resistance should be between 75
65 ohms.
(3) Connect the ohmmeter between terminals 30
and 87A. The ohmmeter should show continuity
between terminals 30 and 87A.
(4) Connect the ohmmeter between terminals 87
and 30. The ohmmeter should not show continuity at
this time.
(5) Connect one end of a jumper wire (16 gauge or
smaller) to relay terminal 85. Connect the other end
of the jumper wire to the ground side of a 12 volt
power source.
(6) Connect one end of another jumper wire (16
gauge or smaller) to the power side of the 12 volt
power source.Do not attach the other end of the
jumper wire to the relay at this time.
WARNING: DO NOT ALLOW OHMMETER TO CON-
TACT TERMINALS 85 OR 86 DURING THIS TEST.(7) Attach the other end of the jumper wire to
relay terminal 86. This activates the relay. The ohm-
meter should now show continuity between relay ter-
minals 87 and 30. The ohmmeter should not show
continuity between relay terminals 87A and 30.
(8) Disconnect jumper wires.
(9) Replace the relay if it did not pass the continu-
ity and resistance tests. If the relay passed the tests,
it operates properly. Check the remainder of the ASD
and fuel pump relay circuits. Refer to group 8W, Wir-
ing Diagrams.
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
To perform a complete test of the MAP sensor and
its circuitry, refer to the DRB scan tool and appropri-
ate Powertrain Diagnostics Procedures manual. To
test the MAP sensor only, refer to the following:
CAUTION: When testing the MAP sensor, be sure
that the harness wires are not damaged by the test
meter probes.
(1) Test the MAP sensor output voltage at the
MAP sensor connector between terminals 2 and 3
(Fig. 95). With the ignition switch ON and the engine
not running, output voltage should be 4 to 5 volts.
The voltage should drop to 1.5 to 2.1 volts with a hot,
neutral idle speed condition. If OK, go to next step. If
not OK, go to step 3.
(2) Test PCM terminal 36 for the same voltage
described in the previous step to verify wire harness
condition. Repair as required.
(3) Test the MAP sensor ground circuit at sensor
connector terminal 1 and PCM terminal 43. If OK, go
to next step. If not OK, repair as required.
(4) Test MAP sensor supply voltage between sen-
sor connector terminals 2 and 1 with the key ON.
The voltage should be approximately 5 volts (6.5V).
Five volts (6.5V) should also be at terminal 61 of the
Fig. 94 ASD and Fuel Pump Relay Terminals
Fig. 95 MAP Sensor Connector
14 - 60 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)