sensor DODGE TRUCK 1993 Service Manual Online

8W - 126
WIRING
DIAGRAMS
SMALL
INDEX
50 49 48
47
46 45
44 43 42 41
40 39
38 37
36 35
34 33 32
© 31
30 29
28 27
26
© 25
24 23
22 21
20 ©
19 18
17
16 15 14 13 12 11 10 9 8 7
6 5 4
3 2
1
LARGE

INDEX TERMINAL END
OF DISCONNECT
ENGINE COMPARTMENT CAVITY

1

10
11
12
13
14 15
16
17
18 19
20
21
22
23
24
25
26
27
28
29
30 31
32 33
34
35
36
37
38
39 40
41
42
43
44
45
46
47
48
50 ENGINE COMPARTMENT CIRCUITS
A3 12RD/WT C7 12BK/TN
A141 16DG/BK
L4
16VT/WT

L3 14RD/0R
V30 20DB/RD
V31 20BR/RD V33
20WT/LG

V32 20YL/RD

E5
20DG/WT

G34 16RD/GY
L20
14LG/WT

G21 20GY/LB G20
20VT/YL

G6 20GY
G60 20GY/YL
G85 20TN/OR
L61 18LG L60 18TN
A15 16PK
T61 20BK/0R
LI 18VT/BK
L7 18BK/YL
F20 18WT
V10 20BR
A41 16YL
X2 18DG/RD
Ml 18BK/TN
Gil
20WT/BK

V5 18DG/YL
V6 18DB
C21 18DB/0R
G3 20BK/PK
X4 20LG/BR V40 18WT/PK
G24 20GY/PK
G7 2GWT/0R T6
200R/WT

V3 18BR/WT
V4 18RD/YL
A21 14DB
A4 12BK/RD Al 12RD
A2 12PK/BK HEADLAMP SWITCH

A/C
AND HEATER BLOWER MOTOR
FUEL PUMP FEED (GAS ONLY)
HEADLAMP LOW BEAM (2 WIRES)
HEADLAMP HIGH BEAM (2 WIRES)
VEHICLE
SPEED
CONTROL
VEHICLE
SPEED
CONTROL VEHICLE
SPEED
CONTROL
VEHICLE
SPEED
CONTROL

WAIT
TO START LAMP (DIESEL
QNLYr

HIGH BEAM INDICATOR LAMP
HIGH BEAM FEED
TACHOMETER SIGNAL (DIESEL)
ENGINE COOLANT TEMPERATURE SENDING
UNIT

ENGINE OIL
PRESSURE
SWITCH
ENGINE OIL
PRESSURE
SENDING
UNIT

WATER-IN FUEL LAMP (DIESEL)
LEFT TURN SIGNAL LAMP RIGHT TURN SIGNAL LAMP
BATTERY-HAZARD FLASHER
TRANSMISSION
OVERDRIVE INDICATOR LAMP
BACK-UP LAMPS
PARKING LAMPS (2 WIRES)
BACK-UP LAMP SWITCH
WINDSHIELD WASHER MOTOR
ENGINE STARTER RELAY
-1GNITI
ON HORN
UNDERHOOD LAMP

ELECTRIC
VACUUM
SENSOR
(DIESEL) (2 WIRES)
WINDSHIELD WIPER MOTOR
WINDSHIELD WIPER MOTOR
AIR CONDITIONING DAMPED
PRESSURE
SWITCH
MALFUNCTION INDICATOR LAMP
4 WHEEL DRIVE SWITCH

BRAKE
SENSOR
SRI
LAMP (GAS ENGINE ONLY)
VEHICLE
SPEED SENSOR

TRANSMISSION
OVERDRIVE
WINDSHIELD WIPER MOTOR
WINDSHIELD WIPER MOTOR
SPLICE-IGNITION RUN CIRCUIT
IGNITION
OFF DRAW

IGNITION
SWITCH
IGNITION
SWITCH
AD 85 50-WAY BULKHEAD DISCONNECT
J938W-11

•

WIRING
DIAGRAMS
8W - 127
CAVITY
INSTRUMENT PANEL CIRCUITS

1

10
11
12

13
14

15

16
17
18
19
20
21
22

23

24
25

26
27
28 29
30 31
31
32

33

34

35

36
37
38
39
40
41
42

43

44

45
46
47
48
49
50
A3
12RD/WT

C7 12BK/TN
A61 16DG/BK
L4
16VT/WT

L3
16RD/0R

V30 20DB/RD
V31 20BR/RD
V33
20WT/LG

V32 20YL/RD
V32 20YL/RD G86
20DG/WT

G34 16RD/GY
L20
20LG/WT

G21 20GY/LB
G20
18VT/YL

G6
20GY

G60 20GY/YL G85
20TN/0R

L61
18LG

L61
18LG

L60
18TN

L60
18TN
A15
16PK

T61 20BK/OR
LI
18VT/BK

L7 18BK/YL
F20
18WT

V10 20BR
A41
14YL

S21 14YL/BK
X2
18DG/R0

Ml
18PK

Gil
20WT/BK
V5
18DG

V6
18DB
C2 18DB/YL
G3 20BK/PK
Gl 20DG/GY
V40
18WT/PK
G24 22GY/PK
G7
20WT/0R
T6
200R/WT

V3 18BR/WT
V4 18RD/YL
A21
14DB

A21
14DB

A4 12BK/RD
Al
12RD

A2 12PK/BK BATTERY FEED

A/C
AND
HEATER BLOWER MOTOR
FUEL PUMP FEED
(GAS
ONLY)
HEADLAMP-LOW BEAM
HEADLAMP-HIGH BEAM VEHICLE
SPEED
CONTROL
VEHICLE
SPEED
CONTROL VEHICLE
SPEED
CONTROL
VEHICLE
SPEED
CONTROL

WAIT
TO
START LAMP (DIESEL ONLY)
HIGH BEAM INDICATOR LAMP
HIGH BEAM FEED (D.R.L. MODULE)
TACHOMETER (DIESEL)
ECT SEND/UNIT
OR
SWITCH
ENGINE
OIL
PRESSURE
LAMP
ENGINE
OIL
PRESSURE
GAUGE-SEND
UNIT

WATER
IN
FUEL LAMP (DIESEL)
LEFT FRONT TURN SIGNAL LAMP
RIGHT FRONT TURN SIGNAL LAMP
HAZARD FLASHER
TRANSMISSION
OVERDRIVE INDICATOR LAMP

BACK-UP
LAMPS

PARKING
LAMPS

BACK-UP
LAMP FEED
WINDSHIELD WASHER MOTOR
IGNITION START
IGNITION START (DIESEL)

HORNS

UNDERHOOD LAMP
ELECTRIC VACUUM
SENSOR
(DIESEL) WINDSHIELD WIPER SWITCH
WINDSHIELD WIPER SWITCH
A/C
COMPRESSOR CLUTCH
MALFUNCTION INDICATOR
4 WHEEL DRIVE SWITCH

BRAKE
SENSOR

SRI
LAMP
(GAS
ENGINE ONLY)
VEHICLE
SPEED
SENSOR
(2
WIRES)
TRANSMISSION
OVERDRIVE SWITCH
WINDSHIELD WIPER
LOW
SPEED

WINDSHIELD WIPER HIGH
SPEED

IGNITION-RUN
I
START
BATTERY FEED IGNITION SWITCH
(Bl)

IGNITION SWITCH
(B3)
SHEET
NO

4,6.30,47
66,67,68 78
43,45,47
36,38
23

43,46
46,47
22
27,28
23

43.45,56
43,45.56

3,5,56
12,14 7.79
43,45,47
7.9
53.55 8,9
30
29
34
54,55 67,69 19,22

13

32,34,36,38
19

19,25
12,14
54.55
10,23.77,78
3.5.39

4,6.10
4.6.10
TERMINAL
END

OF DISCONNECT
ff
p
45 46
47
48 49
50
35 36 37
38 39
40 41
42
43 44
29 30 31
© 32
33 34
23 24
25
© 26
27 28
17 18
19 ©
20 21 22
7 8 9
10 11
12 13
14 15 16
1
^
1.
2
3
4 5 &

J *j

LARGE
INDEX
INSTRUMENT PANEL
J938W-11

50-WAY BULKHEAD
DISCONNECT
AD
86

8W - 130
WIRING
DIAGRAMS

•

1 2 3

A 4

5 6

7
8

/

9
10

11
/


12 13
14

15 16

/

17
18
19
20

21

u
22
23
24

25 26

u

27
28 29

30
31
u

32 33
34

u

35 36

37

38 39
u

40
41 42

u

VIEW FROM WIRE
END
HEADLAMP
I
DASH
WIRING
CAV
IGNITION
SYSTEM CIRCUITS
SHEET
NO

1 A21
14DB
IGNITION
FEED 16
2
Zl 14BK

GROUND
9.68

3

4
LI 18VT/BK BACK-UP LAMPS 9
5 K54 200R/BK
EMCC
SOLENOID
11
6 A141 16DG/BK
FUEL PUMP 16

7
C20
18BR
A/C
COMPRESSOR CLUTCH 18
8 G3 20BK/PK MALFUNCTION INDICATOR LAMP 19
9 A14
16RD
BATTERY FEED 16

10

11
Zll
16BK/WT

SIGNAL GROUND
17

12 V40 18WT/PK
BRAKE
SIGNAL 35
13 Z12 16BK/TN

POWER
GROUND
17
14
T41 18BR/YL ENGINE STARTER RELAY COIL 9
15 G60 20GY/YL ENGINE
OIL
PRESSURE
SEND/UNIT 28
16 G6 20GY
ENGINE
OIL
PRESSURE
SWITCH 28

17 T6
200R/WT
TRANSMISSION
OD
OVERRIDE 12
18 T61 20BK/0R

TRANSMISSION
OD
LAMP SIGNAL
12
19

20
F20
18WT

BACK-UP LAMP SWITCH 9
21
22 T22 14DB/WT
EMCC

11
23

24
G24 20GY/PK
SRI
LAMP
19
25 C13 20DB/0R
A/C
COMPRESSOR CLUTCH RELAY
18
26 G20
20VT/YL
ECT SEND/UNIT
28

27
V31 20BR/RD VEHICLE
SPEED
CONTROL-
SET
35
28 V32 20YL/RD VEHICLE
SPEED
CONTROL- OFF/ON
35
29 V33
20WT/LG
VEHICLE
SPEED
CONTROL- RESUME 35

30
V35 20LG/RD VEHICLE
SPEED
CONTROL- VENT
35
31 V36 20TN/RD VEHICLE
SPEED
CONTROL- VACUUM
35
32
33 G7
20WT/0R
VEHICLE
SPEED
SENSOR 19

34
C3 14DB/BK
A/C
COMPRESSOR CLUTCH FEED 68
35
36

37

38
39

40

41
42
&

GjCUQjQ

UXJUXj
O

"IT
mJKXTV
ENGINE WIRING

- ENG

AD
89
GAS
ENGINE WIRING CONNECTOR
J938W-11

9
- 12
ENGINES

•
CONDITION

POSSIBLE
CAUSES
CORRECTION

EXCESSIVE
EXHAUST

SMOKE
(Cont'd)
More
than
one
sealing washer
under an injector.
Check
and remove
extra
washer.
Improperly operating injectors.
Check
and replace inoperative injectors.
Improperly operating or over-
fueled injection pump.
Replace
injection pump.

Piston
rings
not sealing
(blue smoke). Perform blow-by check. Correct as required.

ENGINE
WILL
NOT

SHUT-OFF
Fuel shutoff valve inoperative.

Engine
running on fumes drawn into the air intake.
Stop
the engine mechanically
with
lever on the
fuel
pump.

Check/replace
sealing washer, piston and
spring.

Check
the air intake ducts for the source of the fumes.
WARNING:
In
ease
of engine runaway due to flammable
fumes

from gasoline spills or turbocharger oil leaks
being
sucked
into the
engine,
shut off engine ignition switch first then use a CO* or dry
chemical type
fire
extinguisher
and direct the
spray
under
the
front
bumper to
remove
oxygen
supply. The engine air
intake
is on the

passenger
side
behind the bumper. The
fire
extinguisher
must
bo
directed at this location for emergency shutdown conditions.

COOLANT
TEMPERA­

TURE
ABOVE
NORMAL
Low
coolant level.
(a) Check coolant level. Add coolant, if necessary.
(b) Locate and correct the source of the coolant leak. Refer to
troubleshooting
logic for coolant
loss.

Incorrect/improperly operating

pressure
cap.
Replace
cap
with
the correct rating for the
system.

High
lube oil level.
Check/drain
oil to correct level.

Loose
drive belt on water

pump/fan.
Check/replace
belt or belt tensioner.
Inadequate air flow to the radiator. Check/repair radiator core, fan shroud and fan clutch as
required.

Radiator
fins
plugged.
Blow
debris from fins.

Collapsed
radiator
hose.
Replace
the
hose.

Improperly operating tempera­

ture
sensor/gauge.
Verify
that
the
gauge
and temperature
sensor
are accurate.

Replace
gauge/sensor,
if bad.
Improperly operating, incorrect

or
no thermostat.
Check
and replace the thermostat.

Air
in the cooling
system.
(a) Make sure the
fill
rate
is not being exceeded and the correct
vented thermostat is installed.
(b) Check for loose hose
clamps.
Tighten if
loose.

(c) If aeration continued, check for a
compression
leak through the head gasket.
Inoperative water pump.
Check
and replace the water pump.
incorrect injection pump timing. Verify pump timing marks are aligned. Check/time the injector

pump
(refer
to Group 7,
Cooling
System).
J9209-56
SERVICE DIAGNOSIS (DIESEL ENGINE) - PERFORMANCE (CONT.)

•

ENGINES
9 - 13

CONDITION
POSSIBLE
CAUSES
COfiiiECTION

COOLANT
TEMPERA­

TURE
ABOVE
NORMAL
(Cont'd)
Overfueled injection pump.

Plugged
cooling
passages
in
radiator, head, head gasket or

block.

Engine
overloaded.
Replace
the injection
pump.

Flush
the
system
and
fill
with
clean coolant.
Verify
that
the engine load rating is not being exceeded.

COOLANT
TEMPERA­

TURE
BELOW
NORMAL
Too
much air flow
across
the
radiator.
Incorrect thermostat, broken
thermostat jiggle pin or

contamination
in thermostat.
Temperature
sensor
or
gauge
inoperative.

Coolant
not flowing by
temperature
sensor.
Check/repair
viscous
fan as required.

Check
and replace thermostat.
Verify
that
the
gauge
and
sensor
are accurate. If not, replace

gauge/sensor.

Check
and clean coolant
passages.

J9109-254
SERVICE DIAGNOSIS (DIESEL ENGINE) • PERFORMANCE (CONT.)

5.9L
(DIESEL)
ENGINE
9 - 155
TORQUE SPECIFICATIONS (CONT.)

COMPONENT

TORQUE

24 N-m 18 ft. lbs.

Trans
Kickdown Cable
Bracket
Mounting/Trans
68 N-m 50 ft. lbs.
68 N-m 50 ft. lbs.
68 N-m 50 ft. lbs.
41 N-m 30 ft. lbs.
54 N-m 40 ft. lbs.

Transmission
Oil Cooler
Line
Flange........
......... .. ......
6
N-m
(50
in.
lbs.)

Transmission
Oil to Air Cooler
Hose
Clamps
2
N-m
(18 in. lbs.)

Transmission
to
Clutch
Housing
Mounting
• 47 N-m
35 ft. lbs.

Transmission
Torque
Converter
Mounting
47 N-m 35 ft. lbs.

Turbine
Housing
11
N-m 8 ft. lbs.

Turbo
Compressor
Housing
Clamp
8.5 N-m (75
in.
lbs.)

Turbo
Mounting
Nut 32 N-m 24 ft. lbs.

Turbo
Oil
Drain
Tube
• 24 N-m
18 ft. lbs.

Turbo
Oil
Supply
(Both
Ends)
.
15
N-m

11
ft.
lbs.
Vacuum
Pump
Mounting
9
N-m
7 ft. lbs.

Vacuum Pump to
Gear
Housing
Mounting
77 N-m 57 ft. lbs.

Valve
Cover.
24 N-m
18 ft. lbs.

Vibration
Damper
Mounting
125 N-m
92 ft. lbs.
Water
Hose
Clamps
4 N-m (35
in.
lbs.)
Water
Inlet
Connection
43 N-m
32 ft. lbs.
Water
Pump
Mounting
24 N-m
18 ft. lbs.
Water
Temperature
Sensor
50 N-m 37 ft. lbs.

J9109-263

EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 19

EXHAUST

MANIFOLD
GASKET

J9111-52
Fig.
6 Air intake Pipe,
Exhaust
Pipe and
Turbocharger
,
till
TURBOCHARGER,

OIL SUPPLY
UNE

^J9111-53

Fig.
7
OH
Supply Line and Charge Air Cooler (intercooler) inlet
Duct

(3) Position the charge air cooler (intercooler) inlet
duct to the turbocharger. With the clamp in position,
tighten the clamp nut to 8 Nun (72 in. lbs.) torque.
(4) Position the air intake pipe and the exhaust
pipe onto the turbocharger. Tighten the clamps to 8 Nun (74 in. lbs.) torque.
(5) Install the oil drain tube and oil supply line to
the turbocharger. Tighten the drain tube bolts to 24
J9111-5

Fig.
8
Engine
Exhaust
Manifold and
Gaskets

EXHAUST

MANIFOLD^^^^
GASKET

J9111-6

Fig.
9
Engine
Exhaust
Manifold
Bolt
Tightening
Sequence

Nun (18 ft. lbs.) torque. Tighten the oil supply line
fitting nut to 15 Nun (11 ft. lbs.) torque. (6) Connect the cab heater supply and return lines.
Tighten the line nuts to 24 Nun (18 ft. lbs.) torque. (7) Operate the engine to check for leaks.
INTAKE MANIFOLD COVER / AIR INTAKE HEATER
REMOVAL (1) Remove the charge air cooler (intercooler) out­
let duct from the air inlet tube (Fig. 10). (2) Remove the high pressure fuel lines. (3) Disconnect and remove the air intake heater
ground wire (Fig. 10). (4) Disconnect the air intake heater power supply
lines (Fig. 11). Remove the air intake heater and
gaskets (Fig. 11). Clean the mounting surface of the
intake manifold cover. (5) Disconnect the charge air temperature sensor
from the intake manifold cover (Fig. 12). (6) Disconnect the air temperature switch from the
intake manifold cover (Fig. 12).

11-20 EXHAUST
SYSTEM
AND
INTAKE MANIFOLD
AIR INLET
INTERCOOLER/ OUTLET DUCT
X^l
/J9111-54.

Fig.
10 Air Inlet Tube and Heater
Ground
Wire
J9111-51

Fig.
11 Air Intake Heater (7) Disconnect the fuel heater ground wire from in­
take manifold cover (Fig. 13).
(8) Remove the manifold intake cover and gasket
(Fig. 13). Keep the gasket material and any other
material out of the air intake.
(9) Clean the sealing surface.

INSTALLATION
(1) Using a new gasket, install the intake manifold
cover. (2) Install the fuel heater ground wire. Tighten the
bolt to 12 Nun (110 in. lbs.) torque.
(3) Connect the air temperature switch to the in­
take manifold cover.
(4) Connect the charge air temperature sensor to
the intake manifold cover.
AIR
TEMPERATURE
SWITCH

(KSB
SOLENOID)

J9114-235

Fig.
12
Charge
Air
Temperature
Sensor
and Air
Temperature
Switch

AAANIFOLD INTAKE COVER FUEL HEATER
GROUND WIRE

J9111-50

Fig.
13 Manifold Intake
Cover
and
Fuel
Heater
Ground
Wire
(5) Some of the intake manifold bolt holes are
drilled through and must be sealed. Apply liquid te­
flon sealant to the bolts. Install the intake manifold
cover bolts. Tighten the bolts to 24 Nun (18 ft. lbs.)
torque.
(6) Install a new gasket between the air intake
heater and the intake manifold cover. Install a new gasket on top of the air intake heater.
(7) Install the air inlet tube. Tighten the air inlet
tube bolts to 24 Nun (18 ft. lbs.) torque. (8) Connect the intake manifold heater ground

wire.
(9) Install and tighten the air intake heater power
supply nuts to 14 Nun (10 ft. lbs.) torque. (10) Position the charge air cooler (intercooler) out­
let duct onto the air inlet tube. Tighten the charge air cooler (intercooler) outlet duct clamps to 8 Nun (74 in. lbs.) torque. (11) Install and bleed the high pressure fuel lines.
Tighten the high pressure fuel line nuts to 24 Nun (18 ft. lbs.) torque.

•

FUEL
SYSTEM
14-29
MULTI-PORT
FUEL
INJECTION
(MPI)-COMPONENT DESCRIPTION/SYSTEM
OPERATION-EXCEPT DIESEL

INDEX

page

Air
Conditioning (A/C) Clutch
Relay-Pern
Output
. 35

Air
Conditioning (A/C)
Controls—PCM
Input
.... 31

Auto
Shut
Down
(ASD)
Relay-PCM
Output
. ... 36

Automatic
Shut
Down
(ASD)
Sense-PCM
Input
. 31
Battery
Voltage-PCM
Input
32

Brake
Switch-PCM
Input
32

Camshaft
Position
Sensor—PCM
Input
32

Charge
Air
Temperature
Sensor—PCM
Input
. . . 32

Crankshaft
Position
Sensor-PCM
Input
.......
32
Electric
Exhaust
Gas Recirculation Transducer
(EET)
Solenoid-PCM
Output
...
.......
36

Engine
Coolant Temperature
Sensor—PCM
Input
. 33

EVAP
Canister
Purge
Solenoid—PCM
Output
. . . 37

Fuel
Injectors-PCM Output
37
Fuel
Pressure
Regulator
41

Fuel
Rail
41

General
Information
.......................
29

Generator
Field-PCM
Output
36

Generator
Lamp-PCM
Output
36
Idle
Air
Control
(IAC)
Motor-PCM
Output
......
36

Ignition
Circuit
Sense—PCM
Input
33

GENERAL
INFORMATION
All
gas
powered engines
are
equipped with sequen­
tial Multi-Port Fuel Injection (MPI).
The MPI
system (Fig.
1)
provides precise air/fuel ratios
for all
driving
conditions. The Powertrain Control Module
(PCM)
operates
the fuel system.
The PCM was
formerly referred
to
as
the
SBEC
or
engine controller.
The PCM is a
pre­
programmed, dual microprocessor digital computer. It regulates ignition timing, air-fuel ratio, emission
control devices, charging system, speed control,
air
conditioning compressor clutch engagement
and
idle speed.
The PCM can
adapt
its
programming
to
meet
changing operating conditions.
Powertrain Control Module (PCM) Inputs rep­
resent
the
instantaneous engine operating conditions.
Air-fuel mixture
and
ignition timing calibrations
for

various driving
and
atmospheric conditions
are
pre­
programmed into
the PCM. The PCM
monitors
and
analyzes various inputs.
It
then computes engine fuel
and ignition timing requirements based
on
these
in­

puts.
Fuel delivery control
and
ignition timing will
then
be
adjusted accordingly. Other inputs
to the
PCM
are
provided
by the
brake
light switch,
air
conditioning select switch
and the

speed control switches.
All
inputs
to the PCM are

converted into signals. Electrically operated fuel injectors spray fuel
in

precise metered amounts into
the
intake port directly above
the
intake valve.
The
injectors
are
fired
in a

specific sequence
by the PCM. The PCM
maintains
page

Ignition
Coil-PCM
Output
37

Malfunction Indicator
Lamp—PCM
Output
37

Manifold
Absolute
Pressure
(MAP)
Sensor-
PCM
Input
33

Open
Loop/Closed
Loop
Modes
of
Operation
. . . 38

Overdrive/Override
Switch
34

Oxygen
(02)
Sensor—PCM
Input
33

Park/Neutral
Switch—PCM
Input
34

Power
Ground
34

Powertrain Control Module
(PCM)
30

SCI
Receive-PCM
Input
. 34

SCI
Transmit-PCM
Output
37

Sensor
Return
—PCM
Input
35

Shift Indicator-PCM Output
38

Speed
Control-PCM
Input
34
Speed
Control-PCM
Output
38

SRI
Lamp-PCM
Output
36

Tachometer—PCM
Output
38

Throttle
Body
40

Throttle
Position
Sensor
(TPS)-PCM
Input
35

Vehicle
Speed
Sensor-PCM
Input
35

an air/fuel ratio
of 14.7 to 1 by
constantly adjusting
injector pulse width. Injector pulse width
is the

length
of
time that
the
injector opens
and
sprays fuel into
the
chamber.
The PCM
adjusts injector pulse
width
by
opening
and
closing
the
ground path
to the
injector.
Manifold absolute pressure
(air
density)
and
engine
rpm (speed)
are the
primary inputs that determine
fuel injector pulse width.
The PCM
also monitors
other inputs when adjusting air-fuel ratio.
Inputs That Effect Fuel Injector Pulse Width:
• Exhaust
gas
oxygen content
• Coolant temperature
• Manifold absolute pressure (MAP)
• Engine speed
• Throttle position
• Battery voltage •
Air
conditioning selection
• Transmission gear selection (auto, trans.)
• Speed control The powertrain control module (PCM) adjusts igni­
tion timing
by
controlling ignition coil operation.
The

ignition coil receives battery voltage when
the
igni­
tion
key is in the run or
starter (crank) position.
The

PCM provides
a
ground
for the
ignition coil.
The
coil
discharges when
the PCM
supplies
a
ground.
By
switching
the
ground path
on and off, the PCM
reg­
ulates ignition timing.
The sensors
and
switches that provide inputs
to the

powertrain control module
(PCM)
comprise
the En-

14
- 30
FUEL
SYSTEM

INPUTS

OUTPUTS
POWERTRAIN
CONTROL
MODULE
DRB
II

SCAN
TOOL

SPEED

CONTROL

BRAKE

SWITCH
A/C
LOW

PRESSURE
CUTOFF
SWITCH VEHICLE

SPEED
SENSOR PARK/NEUTRAL
SWITCH TORQUE CONVERTER
CLUTCH SOLENOID
MALFUNCTION

INDICATOR
LAMP
m
HEATED
i

*OXYGEN SENSOR ENGINE
COOLANT
yy
BATTERY
TEMPERATURE

SENSOR
MAP SENSOR

i—r
CHARGE
AIR
TEMPERATURE
SENSOR
AIR CHARGE
TEMPERATURE
SENSOR
DISTRIBUTOR

WITH
CAMSHAFT
r
POSITION
SENSOR
(|
TACHOMETER

A/C
CLUTCH RELAY
AUTO
SHUTDOWN
RELAY OVERDRIVE
SOLENOID
IDLE AIR
CONTROL MOTOR
SPEED

CONTROL
SHIFT

INDICATOR

LAMP

EMISSION

CONTROL SOLENOIDS
IGNITION
COIL
OVERDRIVE
OVERRIDE SWITCH
ASD

SENSE
FUEL
INJECTORS
PARK
THROTTLE

SOLENOID
GENERATOR CRANKSHAFT
POSITION FUEL
PUMP
RELAY
J9314-117

Fig.
1 Multi-Port
Fuel
Injection
Components—Except
Diesel

gine Control System. It is also comprised of the PCM Outputs (engine control devices that the are operated
by the PCM).

SYSTEM DIAGNOSIS
The powertrain control module (PCM) tests many
of its own input and output circuits. If a diagnostic
trouble code (DTC) is found in a major system, this information is stored in the PCM memory. Refer to
On-Board Diagnostics in the Multi-Port Fuel Injec­
tion—General Diagnosis—Except Diesel section of
this group for DTC information.

POWERTRAIN
CONTROL MODULE (PCM)
The Powertrain Control Module (PCM) (Fig. 2) op­
erates the fuel system. The PCM was formerly re­
ferred to as the SBEC or engine controller. The PCM is a pre-programmed, dual microprocessor digital computer. It regulates ignition timing, air-fuel ratio, emission control devices, charging system, speed con­trol, air conditioning compressor clutch engagement
A/C
CLUTCH RELAY STARTER RELAY
TORQUE CONVERTER CLUTCH RELAY
AUTO
SHUTDOWN RELAY
FUEL PUMP RELAY
DATA UNK
CONNECTOR
POWERTRAIN

CONTROL MODULE
J9314-164

Fig.
2 Powertrain Control
Module
(PCM) Location and idle speed. The PCM can adapt its programming
to meet changing operating conditions.
The PCM receives input signals from various
switches and sensors. Based on these inputs, the
PCM regulates various engine and vehicle operations