trols the horn relay based on a signal received from
the horn switch or active feature (Remote Keyless
Entry (RKE) horn chirp, Vehicle Theft Alarm, Panic).

• Horn - The two horns are located on the left

side of the frame near the lower control arm.

• Horn Relay and Fuse - Located in the Power

Distribution Center (PDC).

• Horn Switch - The horn switch is integral to

the driver airbag.

OPERATION

The Body Control Module (BCM) handles the horn

switch input and controls the horn output. There is a
horn protection feature in the BCM that will not
allow the horns to function if the switch input is
“CLOSED” for more than 30 seconds. Once the
switch is “OPEN”, a 23 second delay will occur before
the horns are functional again.

The horn output operates on battery current

received through a fuse in the Power Distribution
Center (PDC). The horn system circuit is designed so

that the system will remain operational, regardless
of the ignition switch position.

DIAGNOSIS AND TESTING - HORN SYSTEM

Any diagnosis of the Horn system should

begin with the use of a scan tool and the appro-
priate Diagnostic Service Manual.

Refer to the appropriate wiring information.
In most cases, any problem involving continually

sounding horns can be quickly alleviated by removing
the horn fuse from the Power Distribution Center
(PDC).

WARNING:

DISABLE

THE

AIRBAG

SYSTEM

BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.

HORN

8H - 1

HORN

DIAGNOSIS AND TESTING - HORN

Any diagnosis of the Horn system should

begin with the use of a scan tool and the appro-
priate Diagnostic Service Manual.

Refer to the appropriate wiring information.

WARNING:

DISABLE

THE

AIRBAG

SYSTEM

The horn system is separated into two parts: Horn

switch input and the horn relay output.

1. Using a scan tool, check to see if the Body Con-

trol Module senses the horn switch input. If the
input is not OK, then check the wiring between the
horn switch and the BCM.

2. Using a scan tool, actuate the horn relay. If the

relay activates, then check the wiring/fuse from the
Power Distribution Center (PDC) to the horns.

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Raise

vehicle

(Refer

LUBRICATION

MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).

(3) Disconnect electrical harness connectors (Fig.

1).

(4) Remove mounting fastener and horns.

INSTALLATION

(1) Install horns and mounting fastener.
(2) Connect electrical harness connectors.
(3) Lower vehicle.
(4) Connect battery negative cable.

HORN SWITCH

DESCRIPTION

The horn switch is integral to the driver airbag.

The horn switch can not be serviced separately. For
service procedures, (Refer to 8 - ELECTRICAL/RE-
STRAINTS/DRIVER AIRBAG - REMOVAL).

Fig. 1 HORNS

8H - 2

HORN

IGNITION CONTROL

TABLE OF CONTENTS

page

IGNITION CONTROL

DESCRIPTION - IGNITION SYSTEM

. . . . . . . . . . 1

OPERATION - IGNITION SYSTEM

. . . . . . . . . . . 1

SPECIFICATIONS

TORQUE

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

SPARK PLUG

. . . . . . . . . . . . . . . . . . . . . . . . . 2

CABLES RESISTANCE CHART

. . . . . . . . . . . . 2

IGNITION COIL RESISTANCE - 8.3L

. . . . . . . . 2

8.3L - FIRING ORDER

. . . . . . . . . . . . . . . . . . . 2

CAMSHAFT POSITION SENSOR

OPERATION - 8.3L

. . . . . . . . . . . . . . . . . . . . . . . 3

REMOVAL

REPLACING WITH NEW SENSOR

. . . . . . . . . 3

REPLACING OLD SENSOR WITH ORIGINAL

. 4

INSTALLATION

INSTALLATION - WITH NEW SENSOR

. . . . . . 4

REPLACING OLD SENSOR WITH ORIGINAL

. 4

IGNITION COIL

OPERATION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

REMOVAL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

INSTALLATION

. . . . . . . . . . . . . . . . . . . . . . . . . . 6

SPARK PLUG

DESCRIPTION

. . . . . . . . . . . . . . . . . . . . . . . . . . 7

OPERATION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

REMOVAL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

INSTALLATION

. . . . . . . . . . . . . . . . . . . . . . . . . . 7

SPARK PLUG CABLE

DESCRIPTION

. . . . . . . . . . . . . . . . . . . . . . . . . . 7

REMOVAL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

INSTALLATION

. . . . . . . . . . . . . . . . . . . . . . . . . . 8

STARTER BUTTON

REMOVAL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

INSTALLATION

. . . . . . . . . . . . . . . . . . . . . . . . . 10

IGNITION CONTROL

DESCRIPTION - IGNITION SYSTEM

NOTE: All engines use a fixed ignition timing sys-
tem. Basic ignition timing is not adjustable. All
spark advance is determined by the Powertrain
Control Module (PCM).

The distributorless ignition system used on these

engines is referred to as the Direct Ignition System
(DIS). The system’s three main components are the
coils, crankshaft position sensor, and camshaft posi-
tion sensor.

OPERATION - IGNITION SYSTEM

The crankshaft position sensor and camshaft posi-

tion sensor are hall effect devices. The camshaft posi-
tion sensor and crankshaft position sensor generate
pulses that are inputs to the PCM. The PCM deter-
mines engine position from these sensors. The PCM
calculates injector sequence and ignition timing from
crankshaft & camshaft position. For a description of
both sensors, refer to Camshaft Position Sensor and
Crankshaft Position Sensor.

SPECIFICATIONS

TORQUE

DESCRIPTION

N·m

Ft. Lbs.

In. Lbs.

Camshaft Position Sensor

Screw

10.7

Crankshaft Position Sen-

sor Screw

10.7

Ignition Coil to Cyl. Head

Screw

10.7

Spark Plugs

IGNITION CONTROL

8I - 1

Content .. 66 67 68 69 ..