Step
| Action
| Value(s)
| Yes
| No
|
1
| Inspect the horn fuse (Fuse 24) for an open.
Is the horn fuse open?
| --
| Go to
Step 2
| Go to
Step 3
|
2
|
- Remove the horn relay (Relay 15).
- Using a test lamp, frontprobe the underhood accessory wiring junction
block between terminals 740 and BATT, where the fuse was.
Does the test light illuminate?
| --
| Go to
Step 4
| Go to
Step 5
|
3
|
- Disconnect the horn assembly connector.
- Using a test light, probe between circuit 29 and circuit 1350
at the horn assembly connector.
- Press the horn switch while observing the test light.
Does the test light illuminate?
| --
| Go to
Step 8
| Go to
Step 9
|
4
| Replace the underhood accessory wiring junction block.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
5
|
- Leave the test light in the same location.
- Re-install the horn relay.
Does the test light illuminate?
| --
| Go to
Step 12
| Go to
Step 6
|
6
|
- Leave the test light in the same location.
- Disconnect the horn assembly connector.
- Press the horn switch.
Does the test light illuminate?
| --
| Go to
Step 7
| Go to
Step 8
|
7
| Repair a short to ground in circuit 29, between the underhood
accessory wiring junction block connector C3 terminal C8 and
the horn assembly terminal B.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
8
| Replace the horn assembly. Refer to
Horn Replacement
.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
9
|
- Remove the horn relay (Relay 15).
- Using a test light, frontprobe between each 740 circuit
and ground.
Does the test light illuminate for both 740 circuits?
| --
| Go to
Step 10
| Go to
Step 4
|
10
|
- Using a test light, probe between circuit 29 and circuit 350
at the horn assembly connector.
- Momentarily connect a 5A fused jumper between the horn relay terminals
between circuit 29 and circuit 740, of the accessory wiring
junction block while observing the test light.
Does the test light illuminate?
| --
| Go to
Step 11
| Go to
Step 19
|
11
|
- Using a test light, front probe between circuit 28 and
circuit 740 (on the underhood accessory wiring junction block).
- Press the horn switch while observing the test light.
Does the test light illuminate?
| --
| Go to
Step 12
| Go to
Step 13
|
12
| Replace the horn relay. Refer to
Horn Relay Replacement
.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
13
|
- Leave the test light in the same location
- Disable the supplemental inflatable restraint (SIR) System. Refer
to
Disabling the SIR System
in SIR.
- Remove the horn switch wires from the steering wheel.
- Leave the test light connected between circuit 28 and circuit 740
(from the previous step).
- Momentarily connect a 5A fused jumper from ground to the spring
loaded terminal leading towards C201 (at base of steering column).
Did the test light illuminate?
| --
| Go to
Step 14
| Go to
Step 16
|
14
| Inspect for a poor connection of the horn switch ground to steering.
Is there a poor connection?
| --
| Go to
Step 23
| Go to
Step 15
|
15
| Replace the horn switch. Refer to
Inflatable Restraint Steering Wheel Module Replacement
in SIR.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
16
|
- Disconnect the underhood accessory wiring junction block connector C2.
- With a test light frontprobe between circuit 28 and circuit 740
(on the underhood accessory wiring junction block).
- Momentarily connect a 5A fused jumper between the underhood accessory
wiring junction block where connector C2 terminal F7 was and
ground.
Did the test light illuminate?
| --
| Go to
Step 17
| Go to
Step 4
|
17
|
- Reconnect the horn assembly connector.
- Re-install the horn relay.
- Momentarily connect a 5A fused jumper between the underhood accessory
wiring junction block where connector C2 terminal F7 was and
ground.
Did the horn sound?
| --
| Go to
Step 18
| Go to
Step 12
|
18
| Repair an open in circuit 28.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
19
|
- Disconnect the underhood accessory wiring junction block connector C3.
- Using a test light, frontprobe between circuit 29 and circuit 740
(on the underhood accessory wiring junction block.
- Momentarily connect a 5A fused jumper between the underhood accessory
wiring junction block where connector C3 terminal C8 was and
ground.
Did the test light illuminate?
| --
| Go to
Step 20
| Go to
Step 4
|
20
| Using a test light, probe between the horn assembly connector terminal A
and B+.
Does the light illuminate?
| --
| Go to
Step 21
| Go to
Step 22
|
21
| Repair an open in circuit 1350.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
22
| Repair an open in circuit 29.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
23
| Repair a poor connection from the horn switch ground circuit to the
steering wheel.
Is the repair complete?
| --
| Go to
Horns System Check
| --
|
