relay in the Junction Block. When the horn switch is
depressed, it completes the ground circuit. Then the
horn relay coil closes a set of contacts which allows
current to flow to the horns.

DIAGNOSIS AND TESTING - HORN SYSTEM

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.

CAUTION: Continuous sounding of horns will cause
horn to fail.

Check fuse 18 in the Junction Block and fuse L in

the Power Distribution Center. Refer to Horn System
Test table.

HORN SYSTEM TEST

CONDITION

POSSIBLE CAUSE

CORRECTION

HORN SOUNDS CONTINUOUSLY.

NOTE: IMMEDIATELY UNPLUG HORN

AND RELAY IN THE JUNCTION

BLOCK

1. FAULTY HORN RELAY.

1. REFER TO HORN RELAY TEST.

2. HORN CONTROL

CIRCUIT TO RELAY

SHORTED TO GROUND.

2. CHECK HORN RELAY TERMINAL

7 IN JUNCTION BLOCK FOR

CONTINUITY TO GROUND

INDICATES:

A. WIRING HARNESS SHORTED TO

GROUND.

B. FIND THE SHORT AND REPAIR

AS NECESSARY.

HORN

8H - 1

CONDITION

POSSIBLE CAUSE

CORRECTION

3. HORN RELAY CONTROL
CIRCUIT X3 SHORTING TO

GROUND INSIDE

STEERING WHEEL.

3. REMOVE DRIVER AIRBAG

MODULE AND CHECK FOR

RUBBING, SHORTED OR LOOSE

WIRE CONNECTOR AND REPAIR

AS NECESSARY.

4. PINCHED HORN

SWITCH WIRE UNDER

DRIVER AIRBAG MODULE.

4. REPLACE DRIVER AIRBAG

MODULE.

5. FAULTY HORN SWITCH

5. REPLACE DRIVER AIRBAG
MODULE.

HORN SOUND INTERMITTENTLY AS
THE STEERING WHEEL IS TURNED.

1. HORN RELAY CONTROL
CIRCUIT 3 IS SHORTED TO
GROUND INSIDE
STEERING WHEEL.

1. REMOVE DRIVER AIRBAG
MODULE AND CHECK FOR
RUBBING OR LOOSE WIRE/
CONNECTOR, REPAIR AS
NECESSARY.

2. PINCHED HORN
SWITCH WIRE UNDER
DRIVER AIRBAG MODULE.

2. REPLACE DRIVER AIRBAG
MODULE.

3. FAULTY HORN SWITCH.

3. REPLACE DRIVER AIRBAG
MODULE.

HORN DOES NOT SOUND

1. CHECK FUSE 18 IN THE
JUNCTION BLOCK.

1. REPLACE FUSE IF BLOWN AS
REPAIR AS NECESSARY.

2. NO VOLTAGE AT HORN
RELAY TERMINALS 1 & 2
AND FUSE IS OK.

2. NO VOLTAGE, REPLACE
JUNCTION BLOCK OR REPAIR AS
NECESSARY.

3. OPEN CIRCUIT FROM
TERMINAL 7 OF THE
RELAY TO HORN SWITCH
X3 CIRCUIT.

3. REPAIR CIRCUIT AS
NECESSARY.

4. FAULTY OR DAMAGED
HORN.

4. VOLTAGE AT HORN WHEN HORN
SWITCH IS PRESSED, REPLACE
HORN.

5. FAULTY HORN SWITCH

5. REPLACE DRIVER AIRBAG
MODULE.

FUSE BLOWS WHEN HORN IS
BLOWN

1. SHORT CIRCUIT IN
HORN OR HORN WIRING

1. REMOVE HORN RELAY, CHECK
FOR SHORTED HORN OR HORN
WIRING. DISCONNECT HORN WIRE
HARNESS TO ISOLATE SHORT
AND REPAIR AS NECESSARY.

FUSE BLOWS WITHOUT BLOWING
HORN

1. SHORT CIRCUIT

1. REMOVE RELAY, INSTALL NEW
FUSE, IF FUSE DOES NOT BLOW
REPLACE HORN RELAY. IF FUSE
BLOWS WITH RELAY REMOVED,
CHECK FOR SHORT TO GROUND
WITH OHMMETER BETWEEN
TERMINALS 1 & 2 AND THE FUSE
TERMINAL. REPAIR AS
NECESSARY.

NOTE: FOR WIRING REPAIRS REFER
TO GROUP 8W, WIRE DIAGRAMS.

8H - 2

HORN

HORN SYSTEM (Continued)

HORN

DIAGNOSIS AND TESTING - HORN

(1) Disconnect wire connector at each horn.
(2) Using a voltmeter, connect one lead to body

ground and the other lead to the horn relay output
pin of the horn connector (Fig. 1).

HORN CONNECTOR PIN CALL-OUT

PIN #

CIRCUIT NAME

GROUND

HORN RELAY OUTPUT

The right horn is grounded on the front outboard

side of the right frame rail. The left horn is grounded
on the left front fender apron.

(3) When the horn switch is depressed, battery

voltage should be present. Repeat for the other horn.

(4) If no voltage, repair as necessary. If battery

voltage is present, go to next step.

(5) Using an ohmmeter, test the negative terminal

of the connector for continuity to ground. Repeat for
the other horn.

(6) If no ground, repair as necessary.
(7) If wires test OK and horn(s) does not sound,

replace horn(s).

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Disconnect wire connector.
(3) Remove the horn bracket mounting bolt and

remove horn.

NOTE: Do not disconnect horn from horn bracket.

INSTALLATION

(1) Position both horns and the mounting bracket

onto the vehicle as a unit.

(2) Install and tighten the screw that secures the

horn mounting bracket to vehicle. Tighten the screw
to 11.3 N·m (100 in. lbs.).

(3) Connect the wire connector.
(4) Connect the battery negative cable.

HORN RELAY

DIAGNOSIS AND TESTING - HORN RELAY

(1) Remove horn relay.
(2) Using ohmmeter, test between relay connector

terminals 85 to 86 for 75 ± 8 ohms resistance. If
resistance not OK, replace relay (Fig. 2).

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Open the driver’s door and remove the left

instrument panel end cover.

(3) Remove the horn relay (Fig. 3).

INSTALLATION

(1) Insert the horn relay.
(2) Install the left instrument panel end cover.
(3) Reconnect the battery negative cable remote

terminal.

Fig. 1 HORN CONNECTOR

Fig. 2 Horn Relay

30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED

HORN

8H - 3

HORN SWITCH

DIAGNOSIS AND TESTING - HORN SWITCH

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.

(1) Using ohmmeter, connect one lead to ground

wire and the other lead to the positive wire (Fig. 4).

(2) Depress horn switch, continuity should be

present. Repeat for other switch. If no continuity,
replace switches.

Fig. 4 HORN SWITCH TEST LOCATIONS

1 - HORN SWITCH CONNECTOR
2 - DO NOT REMOVE NUTS

3 - INSIDE CONNECTOR

Fig. 3 Horn Relay Location

1 - HORN RELAY

8H - 4

HORN

HORN RELAY (Continued)

Content .. 76 77 78 79 ..