brake sensor DODGE TRUCK 1993 Service Owner's Guide

WIRING
DIAGRAMS 8W - 125
5.2L £ 5.9L ENGINE VIEWED FROM WIRE
END OF CONNECTOR

POWERTRAIN
CON

J938W-H
(PCM II) CONNECTOR
CAV

IGNITION
SYSTEM CIRCUITS SHEET

1
Kl
200G/RD
MAP
SENSOR
20
2"-1 K2
20TN/BK
ENGINE COOLANT TEMPERATURE SENSOR
20
3 A14
IBRD
DIRECT BATTERY
16
4 K4 18BK/LB

SENSOR
RETURN
20
5 Zll
16BK/WT

SIGNAL
GROUND
17
6 K6
20VT/WT
5 VOLT SUPPLY
20
7
K7
180R 8 VOLT INPUT
20
8 —
—
9 A21 14DB IGNITION FEED
16
10 T6
200R/WT
TRANSMISSION
OD CONTROL
12
11 Z12 18BK/TN POWER GROUND
17
12 Z12 18BK/TN POWER GROUND
17
13 |Kl4 18LB/BR
INJECTOR DRIVER 4
15
14 K13
18YL/WT

INJECTOR DRIVER 3
15
15 K12 18TN INJECTOR DRIVER 2
15
16
17" Kl1
18WT/DB

INJECTOR DRIVER 1
15
16
17"
K17
18DB/TN
INJECTOR DRIVER 7
15
18 K18
18RD/YL
INJECTOR DRIVER 8
15
19 K19 18GY IGNITION COIL DRIVER
15
20 K20 18DG GENERATOR FIELD DRIVER
19
21 K21
18BK/RD
TB SURFACE TEMP SENSOR
20
22 K22
180R/DB
THROTTLE POSITION (SENSOR)
18
23 K141
18TN/WT
HEATED OXYGEN SENSOR (5.9L HD)
17
24 K24 18GY/BK
REFERENCE
PICKUP
18
25 021
20PK
DATA LINK TRANSMIT
17
26 —
—
27 C20 18BR
A/C
CYCLING SWITCH INPUT
18
28 — _
29 V40
18WT/PK
BRAKE
SENSE

35
30 T41
20BR/YL
PARK/NEUTRAL POSITION SWITCH
19
31 —
—
32 G3
20BK/PK
MALUNCTION INDICATOR LAMP
19
33 V36
20TM/RD

VEHICLE SPEED CONTROL-VACUUM
35
34 C13 20DB/OR W.O.T. CUTOUT RELAY
18
35 K35 20GY/YL
EGR
SOLENOID
16
36 —
— —
37 TBI 20BK/0R
TRANSMISSION
OD LAMP SIGNAL
12
38 K15
18PK/BK
INJECTOR DRIVER 5
15
39
"40 K39 18GY/RD
IDLE AIR CONTROL MOTOR
19
39
"40 K40 18BR/WT IDLE AIR CONTROL MOTOR
19
41 K41
18BK/DG
HEATED OXYGEN SENSOR
17
42
43 —
—
42
43 —
—
—
44 K44 18GY CAMSHAFT POSITION
SENSE

20
45 020 20LG
DATA LINK RECEIVE
17
46 —
— —
47 G7
20WT/OR
VEHICLE SPEED SENSOR PICKUP
20
48 V31
20BR/RD
VEHICLE SPEED CONTROL-SET
35
49 V32
20YL/RD
VEHICLE SPEED CONTROL-ON/OFF
35
50 Y33
20WT/LG
VEHICLE SPEED CONTROL-RESUME
35
51 K51 20DB/YL AUTOMATIC SHUT-DOWN RELAY
16
52 K52
20PK/BK
EVAP/PURGE
SOLENOID
16
53 V35
20LG/RD
VEHICLE SPEED CONTROL-VENT
35
54 K54
200R/BK
EMCC
SOLENOID
11.12
55 T60
200R/LG
TRANSMISSION
OD SOLENOID
12
5G G24
20GY/PK
SERVICE
REMINDER INDICATOR LAMP
13
57 A142 16DG/0R
A.S.D.-
BATTERY
SENSE

15
58 K16 18LG/BK INJECTOR DRIVER 6
15
59 K59 18VT/BK IDLE AIR CONTROL MOTOR
19
60 K60 18YL/BK IDLE AIR CONTROL MOTOR
19

TROL
MODULE II
(GAS
MFI ENGINES) AD 84

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

•

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

•

FUEL SYSTEM
14-31 through different system components. These compo­
nents are referred to as Powertrain Control Module
(PCM) Outputs. The sensors and switches that pro­
vide inputs to the PCM are considered Powertrain Control Module (PCM) Inputs.
The PCM adjusts ignition timing based upon in­
puts it receives from sensors that react to: engine rpm, manifold absolute pressure, engine coolant tem­
perature, throttle position, transmission gear selec­
tion (automatic transmission), vehicle speed and the
brake switch.
The PCM adjusts idle speed based on inputs it re­
ceives from sensors that react to: throttle position,
vehicle speed, transmission gear selection, engine coolant temperature and from inputs it receives from
the air conditioning clutch switch and brake switch.
Based on inputs that it receives, the PCM adjusts
ignition coil dwell. The PCM also adjusts the gener­
ator charge rate through control of the generator
field and provides speed control operation.
Powertrain Control Module (PCM) Inputs:
• Generator output • A/C request (if equipped with factory A/C)
• A/C select (if equipped with factory A/C)
• Auto shut down (ASD) sense
• Charge air temperature sensor
• Battery voltage
• Brake switch
• Engine coolant temperature sensor
• Crankshaft position sensor • Ignition circuit sense (ignition switch in run posi­
tion)
• Manifold absolute pressure (MAP) sensor
• Overdrive/override switch
• Oxygen sensor(s)
• Park/neutral switch (auto, trans, only)
• SCI receive (DRB II connection) • Speed control resume switch
• Speed control set switch • Speed control on/off switch
• Camshaft position sensor signal
• Throttle position sensor
• Vehicle speed sensor
• Sensor return
• Power ground
• Signal ground Powertrain Control Module (PCM) Outputs:
• A/C clutch relay
• Idle air control (IAC) motor
• Auto shut down (ASD) relay
• Generator field
• Malfunction indicator lamp
• Service reminder indicator lamp
• EGR valve control solenoid • Fuel injectors
• Fuel pump relay
• Ignition coil • EVAP canister purge solenoid
• SCI transmit (DRB II connection)
• Shift indicator lamp (manual transmission only)
• Speed control vacuum solenoid
• Speed control vent solenoid
• Tachometer (on instrument panel, if equipped) The powertrain control module (PCM) contains a
voltage convertor. This converts battery voltage to a
regulated 8.0 volts. It is used to power the crankshaft
position sensor and camshaft position sensor. The
PCM also provides a five (5) volt supply for the man­ ifold absolute pressure (MAP) sensor and throttle po­
sition sensor (TPS).

AIR
CONDITIONING
(A/C)
CONTROLS-PCM
INPUT
The A/C control system information applies to fac­
tory installed air conditioning units. A/C SELECT SIGNAL: When the A/C switch is
in the ON position and the A/C low pressure switch
is closed, an input signal is sent to the powertrain
control module (PCM). The signal informs the PCM
that the A/C has been selected. The PCM adjusts idle speed to a pre-programmed rpm through the idle air
control (IAC) motor to compensate for increased en­
gine load. A/C REQUEST SIGNAL: Once A/C has been se­
lected, the powertrain control module (PCM) receives
the A/C request signal from the evaporator switch.
The input indicates that the evaporator temperature is in the proper range for A/C application. The PCM
uses this input to cycle the A/C compressor clutch (through the A/C relay). It will also determine the
correct engine idle speed through the idle air control (IAC) motor position. If the A/C low pressure switch opens (indicating a
low refrigerant level), the PCM will not receive an
A/C select signal. The PCM will then remove the ground from the A/C relay. This will deactivate the
A/C compressor clutch. If the evaporator switch opens, (indicating that
evaporator is not in proper temperature range), the
PCM will not receive the A/C request signal. The
PCM will then remove the ground from the A/C re­ lay, deactivating the A/C compressor clutch.

AUTOMATIC SHUT DOWN
(ASD)
SENSE-PCM INPUT
A 12 volt signal at this input indicates to the PCM
that the ASD has been activated. The ASD relay is located in the engine compartment (Fig. 2). It is used
to connect the oxygen sensor(s) heater element, igni­
tion coil, generator field winding and fuel injectors to 12 volt + power supply. This input is used only to sense that the ASD relay
is energized. If the powertrain control module (PCM)
does not see 12 volts at this input when the ASD
should be activated, it will set a diagnostic trouble
code (DTC).

14
- 32
FUEL SYSTEM

•
BATTERY VOLTAGE—PCM
INPUT

The battery voltage input provides power
to the

powertrain control module (PCM).
It
also informs
the

PCM what voltage level
is
supplied
to the
ignition
coil
and
fuel injectors. If battery voltage
is low, the PCM
will increase injec­
tor pulse width (period
of
time that
the
injector
is
ener­
gized).
This
is
done
to
compensate
for the
reduced flow
through injector caused
by the
lowered voltage.

BRAKE
SWITCH-PCM
INPUT
When
the
brake light switch
is
activated,
the
pow­
ertrain control module
(PCM)
receives
an
input indi­
cating that
the
brakes
are
being applied. After
receiving this input,
the PCM
maintains idle speed
to
a
scheduled
rpm
through control
of the
idle
air
control
(IAC)
motor.
The
brake switch input
is
also
used
to
operate
the
speed control system.

CAMSHAFT POSITION SENSOR—PCM
INPUT
A sync signal
is
provide
by the
camshaft position sen­
sor located
in the
ignition distributor
(Fig.
3).
The
sync
signal from this sensor works
in
conjunction with
the

crankshaft position sensor
to
provide
the
powertrain
control module
(PCM)
with inputs. This
is
done
to es­

tablish
and
maintain correct injector firing order. Refer
to
Camshaft Position Sensor
in
Group
8D, Ig­

nition System
for
more information.

Fig.
3
Camshaft Position
Sensor

CHARGE AIR TEMPERATURE SENSOR-PCM
INPUT
The intake manifold charge
air
temperature sensor
is installed
in the
intake manifold with
the
sensor
el­

ement extending into
the air
stream
(Fig. 4). The
sensor provides
an
input voltage
to the
powertrain control module
(PCM)
indicating intake manifold
air

temperature.
The
input
is
used along with inputs from other sensors
to
determine injector pulse width. As
the
temperature
of the
air-fuel stream
in the
manifold varies,
the
sensor resistance changes. This
results
in a
different input voltage
to the PCM.

Fig.
4
Charge
Air
Temperature
Sensor—Typical

CRANKSHAFT POSITION SENSOR-PCM INPUT
This sensor
is a
hall effect device that detects
notches
in the
flywheel (manual transmission),
or
flexplate (automatic transmission). This sensor
is
used
to
indicate
to the
powertrain
control module
(PCM)
that
a
spark
and or
fuel injec­
tion event
is to be
required.
The
output from this sensor,
in
conjunction with
the
camshaft position
sensor signal,
is
used
to
differentiate between fuel
in­

jection
and
spark events.
It is
also used
to
synchro­ nize
the
fuel injectors with their respective cylinders. The sensor
is
bolted
to the
cylinder block near
the

rear
of the
right cylinder head
(Fig. 5).
Fig.
5
Crankshaft Position Sensor—Typical

•

FUEL
SYSTEM
14-45 (12) Inspect accelerator cable, transmission throt­
tle cable (if equipped) and cruise control cable con­
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or re­ strictions (Fig. 8).

Fig.
8
Throttle
Body
Cables—Typical
(13) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit­
ting on intake manifold. Also check connection to
brake vacuum booster.
(14) Inspect the air cleaner inlet and air filter ele­
ment for dirt or restrictions.
(15) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions. (16) Verify that the intake manifold charge air
temperature sensor wire connector is firmly con­ nected to harness connector (Figs. 9 or 10).

Fig.
9 Air
Temperature
Sensor—3.9L
(V-6)
Engine
(17) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 11). Also verify
that rubber L-shaped fitting from MAP sensor to the
throttle body is firmly connected (Fig. 12).
(18) Verify that fuel injector wire harness connec­
tors are firmly connected to injectors in the correct
Fig.
10 Air
Temperature
Sensor—5.2U5.9L
(V-8)

Engines
MANIFOLD
ABSOLUTE

Fig.
11 MAP Sensor—Typical
order. Each harness connector is numerically tagged
with the injector number (INJ 1, INJ 2 etc.) of its
corresponding fuel injector and cylinder number.
(19) Verify harness connectors are firmly con­
nected to idle air control (IAC) motor, throttle posi­
tion sensor (TPS) and manifold absolute pressure (MAP) sensor (Fig. 11).
(20) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor (Fig. 13).
(21) Raise and support the vehicle.
(22) Verify that oxygen sensor wire connector (or
connectors) are firmly connected to the sensor (or sensors). Inspect sensor(s) and connector(s) for dam­age (Figs. 14 or 15).

CAV

WIRE

COLOR DESCRIPTION
CAV
WIRE

COLOR DESCRIPTION

1 DG/RD*
MAP SENSOR 37
BK/OR OVERDRIVE LAMP
2 TN/BK*
ENGINE COOLANT TEMPERATURE SENSOR 38 PK/BK INJECTOR DRIVE
#5

3 RD/WT DIRECT BATTERY 39 GY/RD IAC MOTOR
#4

4
BK/LB*

SENSOR RETURN 40 BR/WT
IAC MOTOR
#2

5 BK/WT SIGNAL GROUND 41
BK/DG* OXYGEN SENSOR SIGNAL
6 VT/WT
5-VOLT
OUTPUT
(MAP AND TPS)
42
7 OR

8-VOLT
OUTPUT (DISTRIBUTOR PICK-UP) 43

GY/LB*
TACHOMETER SIGNAL OUTPUT (VEHICLES W/TACHOMETER)
8 44 GY CAMSHAFT POSITION SENSE
9 DB
J2-IGNITION FEED 45
LG SCI RECIEVE
10 R/WT OVERDRIVE OVERRIDE
46 CCD
(-)

11 BK/TN POWER GROUND 47 WT/OR* SPEED SENSOR SIGNAL
12 BK/TN POWER GROUND 48 BR/RD* SPEED CONTROL
SET
SWITCH
13 LB/BR
INJECTOR DRIVER
#4
49
YL/RD* SPEED CONTROL ON/OFF SWITCH
14 YL/WT
INJECTOR DRIVER
#3
50 WT/LG* SPEED CONTROL RESUME SWITCH
15 TN INJECTOR DRIVER
#2
51 DB/YL*
AUTO SHUTDOWN
(ASD)
RELAY
-
RETURN
16
WT/DB*

INJECTOR DRIVER
#1
52 PK/BK
EVAP CANISTER PURGE SOLENOID
17 DB/TN INJECTOR DRIVER
#7
(V-8
ONLY) 53 LG/RD* SPEED CONTROL VENT SOLENOID
18 DB/GY
INJECTOR DRIVER
#8
(V-8
ONLY) 54
OR/BK* SHIFT INDICATOR LIGHT (MANUAL TRANSMISSION ONLY)
19 BK/GY*
IGNITION COIL DRIVER 54
OR/BK* CONVERTOR CLUTCH SOLENOID (AUTO TRANSMISSION)
20 DG
GENERATOR FIELD CONTROL 55
OR/WT OVERDRIVE SOLENOID (AUTO TRANSMISSION ONLY)
21 BK/RD
CHARGE TEMPERATURE SENSOR 56
GY/PK SRI LAMP
(5.9L HDC
ENGINE)
22
OR/DB*

THROTTLE POSITION SENSOR
(TPS)
57
DG/OR ASD SENSE
23 TN/WT
OXYGEN SENSOR SIGNAL
(5.9L HDC
ENGINE) 58 LG/BK
INJECTOR DRIVER
#6

24 GY/BK IGNITION (CAMSHAFT POSITION SENSOR) 59
VT/BK IAC MOTOR
#1

25 PK
,
SCI
TRANSMIT 60
YL/BK* IAC MOTOR
#3

26 CCD
(-:-)
WIRE COLOR CODES LB
LIGHT BLUE
VT VIOLET

27 BR
A/C SWITCH SENSE BK BLACK
LG LIGHT GREEN
WT

WHITE
28 VT A/C SELECT BR BROWN
OR ORANGE
YL YELLOW
29 WT/PK* BRAKE SWITCH
-
DB DARK BLUE PK
PINK *
WITH TRACER
30 BY/YL*
PARK/NEUTRAL SWITCH DG DARK GREEN
RD
RED
31 GY
GRAY TN TAN
32 BK/PK*
MALFUNCTION INDICATOR LAMP
33 TN/RD*
SPEED CONTROL VACUUM SOLENOID CONNECTOR
34 DB/OR* A/C CLUTCH RELAY TERMINAL

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35 GY/YL*
EGR SOLENOID SHOWN W'41
30
50«M#5l31
604

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36 J9314-171
Fig.
17 PCM
Connector—Gas
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