Step
| Action
| Value(s)
| Yes
| No
|
DEFINITION: One or both of the horns are inoperative
|
1
| Was the
Horns System Check performed?
| --
| Go to
Step
2
| Refer to
Horns System Check
|
2
|
- Install the scan tool.
- Select the miscellaneous test in special functions.
- Command the BCM to turn ON the horns.
Do both horns sound for as long as the BCM has them turned ON?
| --
| Go to
Step 13
| Go to
Step 3
|
3
|
- Disconnect the horn #1 connector.
- Use the DMM to measure the voltage between terminal 2 of the horn
#1 connector and a known good ground.
- Repeat steps 1 and 2 for horn #2.
Is the measured voltage within the specified value?
| B+
| Go to
Step 5
| Go to
Step
4
|
4
|
- Check the horn fuse for an open.
- If the horn fuse is OK, locate an open or a high resistance in
the following circuits:
- Repair the open or the high resistance in any one of these circuits.
Is the repair complete?
| --
| Go to
Step
17
| --
|
5
|
- Connect the horn #1 and horn #2 connectors.
- Remove the horn relay K63 from the relay box.
- Connect a fused jumper between terminal 4 and terminal 8 of the
relay box.
Do both horns sound?
| --
| Go to
Step
7
| Go to
Step
6
|
6
|
- Locate an open or a high resistance in circuits XM60, XM65, XM70,
XM30 and/or F700.
- Repair the open or the high resistance in any one of these circuits.
- If all of these circuits are OK, replace horn #1 and/or horn #2.
Refer to
Horn Replacement
in Horns.
Is the repair or replacement complete?
| --
| Go to
Step 17
| --
|
7
| Use the DMM in order to measure the voltage
between terminal 2 of the horn relay K63, and a known good ground.
Is the measured voltage within the specified value?
| B+
| Go to
Step 9
| Go to
Step
8
|
8
|
- Locate an open or a high resistance in circuit A121.
- Repair the open or the high resistance in circuit A121.
Is the repair complete?
| --
| Go to
Step
17
| --
|
9
| While commanding the BCM to activate the horns,
use the DMM in order to measure the voltage between terminal 2 and
6 of the horn relay K63.
Is the measured voltage within the specified value?
| B+
| Go to
Step 10
| Go to
Step
11
|
10
| Replace the horn relay K63.
Is the replacement complete?
| --
| Go to
Step
17
| --
|
11
|
- Disconnect the BCM connector C2.
- Use the DMM to measure the resistance between terminal 6 of the
relay box and terminal C4 of the BCM connector C2.
Is the measured resistance less than the specified value?
| 5 ohms
| Go to
Step 16
| Go to
Step 12
|
12
|
- Locate an open or a high resistance in circuit XM899.
- Repair the open or the high resistance in circuit XM899.
Is the repair complete?
| --
| Go to
Step
17
| --
|
13
|
- Remove the horn switch.
- Remove the horn relay K63 from the relay box.
- Connect a jumper between terminal A and terminal B of the horn
switch connector.
- Use the DMM to measure the resistance between terminal 6 of the
relay box and a known good ground.
Is the measured resistance less than the specified value?
| 5 ohms
| Go to
Step 15
| Go to
step 14
|
14
|
- Locate an open or a high resistance in circuits XM1, X1 and/or
F122.
- Repair the open or the high resistance in circuits XM1, X1 and/or
F122.
- Replace the inflatable restraint steering wheel module coil if
these circuits are OK. Refer to
Inflatable Restraint Steering Wheel Module Coil Replacement
in SIR.
Is the repair or replacement complete?
| --
| Go to
Step 17
| --
|
15
| Replace the horn
switch. Refer to
Horn Switch Replacement - On Vehicle
in Steering Wheel and Column On-Vehicle Service.
Is the replacement complete?
| --
| Go to
Step
17
| --
|
16
| Replace the BCM.
Is the replacement complete?
| --
| Go to
Step 17
| --
|
17
|
- Connect all connectors and components that were disconnected.
- Verify that both horns operate properly.
Do both of the horns operate properly?
| --
| System OK
| Go to
Step 1
|