Contents: Signs of malfunction - sound signal ↧ Signs of malfunction - sound signal ↧ The sound signal is constantly on ↧ The sound signal is constantly on ↧ The sound signal does not work ↧ The sound signal does not work ↧
Signs of malfunction - sound signal
Description of the test
The numbers below indicate the item numbers in the diagnostic table.
5. Check that the body control module (BCM) grounds the horn relay.
6. Check the voltage at the positive battery voltage terminal on the horn relay winding.
8. Check the voltage at the battery positive terminal on the horn relay switch. Power is supplied to the battery positive terminal on the horn relay switch via the HORN fuse.
16. Maximum current is required for normal operation of the sound signal. Increased resistance (more than 0.5 Ohm) in the horn control circuit or the horn ground circuit may cause the horn to malfunction. Inspect the circuits for defects that may limit current flow.
18. The horn relay control circuit includes a horn sliding ring and a horn switch. When checking the relay control circuit, check the horn sliding ring and horn switch for high resistance, open circuit, or short circuit to supply voltage.
Signs of malfunction - sound signal
| Step | Operation | Values | Yes | No |
| 1 |
Check fuse F17.
Has the vehicle system diagnostic check been completed?
|
-
|
Go to Step 2
|
Check the vehicle with a diagnostic tool.
|
| 2 |
Is the car equipped with a remote control locking system?
Is the renovation finished?
|
-
|
Go to Step 3
|
Go to Step 4
|
| 3 |
Is the voltage equal to the specified value?
|
-
|
Go to Step 4
|
Go to Step 5
|
| 4 |
Press the horn switch.
Does the sound signal work?
|
-
|
Go to Step 6
|
|
| 5 |
Test the horn relay control circuit portion of the body control module (BCM) for high resistance or an open.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 14
|
| 6 |
Is the indicator light on?
|
-
|
Go to Step 7
|
Go to Step 17
|
| 7 |
Is the indicator light on?
|
-
|
Go to Step 8
|
Go to Step 18
|
| 8 |
Connect a test light between the battery positive voltage circuit at the horn relay switch and a good ground.
Is the indicator light on?
|
-
|
Go to Step 9
|
Go to Step 19
|
| 9 |
Momentarily connect a jumper wire with a 15-amp fuse between the battery positive voltage circuit at the horn relay switch and the horn control circuit.
Does the sound signal work?
|
-
|
Go to Step 15
|
Go to Step 10
|
| 10 |
Is the indicator light on?
|
-
|
Go to Step 11
|
Go to Step 20
|
| 11 |
Is the indicator light on?
|
-
|
Go to Step 12
|
Go to Step 21
|
| 12 |
Inspect the horn for poor contact.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 13
|
| 13 |
Does the sound signal work?
|
-
|
Go to Step 16
|
Go to Step 24
|
| 14 |
Inspect the harness connector at the BCM for poor connections.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 22
|
| 15 |
Inspect the horn relay for poor contact.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 23
|
| 16 |
Eliminate increased resistance in the horn control circuit or horn ground circuit. Even resistance as low as 0.5 ohms can cause horn malfunction.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 17 |
Eliminate the open circuit or increased resistance in the positive battery voltage circuit on the horn relay winding.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 18 |
Important: The horn switch is part of the inflatable airbag module on the steering wheel. See Section 8B, Inflatable Airbag System (SIR).
Eliminate open or short to supply voltage in the horn relay control circuit. The horn relay control circuit includes the horn sliding ring and the horn switch.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 19 |
Repair open or high resistance in the battery positive voltage circuit at the horn relay switch.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 20 |
Eliminate open circuit or high resistance in the horn control circuit.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 21 |
Eliminate open circuit or increased resistance in the ground circuit of the sound signal.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 22 |
Important: Perform the BCM programming procedure when replacing the BCM. Replace the BCM.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 23 |
Replace the horn relay.
Is the replacement complete?
|
-
|
Go to Step 25
|
-
|
| 24 |
Replace the sound signal.
Is the replacement complete?
|
-
|
Go to Step 25
|
-
|
| 25 |
Sound the alarm.
Is the sound signal working properly?
|
-
|
The system is normal
|
Go to Step 25
|
The sound signal is constantly on
Description of the test
The numbers below indicate the item numbers in the diagnostic table.
5. Check if ground is constantly supplied to the horn relay.
6. The horn relay control circuit includes the horn sliding ring and the horn switch. When checking the relay control circuit, it is necessary to check for a short to ground on the horn sliding ring and the horn switch.
The sound signal is constantly on
| Step | Operation | Values | Yes | No |
| 1 |
Has the vehicle system diagnostic check been completed?
|
-
|
Go to Step 2
|
Check the vehicle with a diagnostic tool.
|
| 2 |
Is the car equipped with a remote control locking system?
|
-
|
Go to Step 3
|
Go to Step 4
|
| 3 |
Does the sound signal sound continuously?
|
-
|
Go to Step 4
|
|
| 4 |
Does the sound signal work?
|
-
|
Go to Step 9
|
Go to Step 5
|
| 5 |
Connect a test lamp between the battery positive voltage circuit on the horn relay winding and the horn relay control circuit.
Is the indicator light on?
|
-
|
Go to Step 6
|
Go to Step 7
|
| 6 |
Important: The horn switch is part of the steering wheel air bag module. See. Section 8B, Supplemental Inflatable Restraint System (SIR).
Check the horn relay control circuit for a short to ground.
Has the cause been found and corrected?
|
-
|
Go to Step 12
|
Go to Step 8
|
| 7 |
Inspect the horn relay for poor contact.
Has the cause been found and corrected?
|
-
|
Go to Step 12
|
Go to Step 10
|
| 8 |
Inspect the body control module (BCM) for poor connections.
Has the cause been found and corrected?
|
-
|
Go to Step 12
|
Go to Step 11
|
| 9 |
Eliminate short circuit to supply voltage in the horn control circuit.
Is the renovation finished?
|
-
|
Go to Step 12
|
-
|
| 10 |
Replace the horn relay.
Is the replacement complete?
|
-
|
Go to Step 12
|
-
|
| 11 |
Important: Perform the BCM programming procedure when replacing the BCM. Replace the BCM. See. Section 9V, "Body Controller".
Is the indicator light on?
|
-
|
Go to Step 12
|
-
|
| 12 |
Sound the alarm.
Is the sound signal working properly?
|
-
|
The system is normal
|
Go to Step 1
|
The sound signal does not work
Description of the test
The numbers below indicate the item numbers in the diagnostic table.
5. Check that the body control module (BCM) grounds the horn relay.
6. Check the voltage at the positive battery voltage terminal on the horn relay winding.
8. Check the voltage at the battery positive terminal on the horn relay switch. Power is supplied to the battery positive terminal on the horn relay switch via the HORN fuse.
16. Maximum current is required for normal operation of the sound signal. Increased resistance (more than 0.5 Ohm) in the horn control circuit or the horn ground circuit may cause the horn to malfunction. Inspect the circuits for defects that may limit current flow.
18. The horn relay control circuit includes a horn sliding ring and a horn switch. When checking the relay control circuit, check the horn sliding ring and horn switch for high resistance, open circuit, or short circuit to supply voltage.
The sound signal does not work
| Step | Operation | Values | Yes | No |
| 1 |
Check the vehicle with a diagnostic tool.
|
-
|
Go to Step 2
|
Check the vehicle with a diagnostic tool.
|
| 2 |
Is the car equipped with a remote control locking system?
|
-
|
Go to Step 3
|
Go to Step 4
|
| 3 |
Does the sound signal work?
|
-
|
Go to Step 4
|
Go to Step 5
|
| 4 |
Press the horn switch.
Does the sound signal work?
|
-
|
Checking for intermittent fault
|
Go to Step 6
|
| 5 |
Test the horn relay control circuit portion of the body control module (BCM) for high resistance or an open.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 14
|
| 6 |
Is the indicator light on?
|
-
|
Go to Step 7
|
Go to Step 17
|
| 7 |
Is the indicator light on?
|
-
|
Go to Step 8
|
Go to Step 18
|
| 8 |
Connect a test light between the battery positive voltage circuit at the horn relay switch and a good ground.
Is the indicator light on?
|
-
|
Go to Step 9
|
Go to Step 19
|
| 9 |
Momentarily connect a jumper wire with a 15-amp fuse between the battery positive voltage circuit at the horn relay switch and the horn control circuit.
Does the sound signal work?
|
-
|
Go to Step 15
|
Go to Step 10
|
| 10 |
Is the indicator light on?
|
-
|
Go to Step 11
|
Go to Step 20
|
| 11 |
Is the indicator light on?
|
-
|
Go to Step 12
|
Go to Step 21
|
| 12 |
Inspect the horn for poor contact.
Has the cause been found and corrected?
|
-
|
Go to Step 25
|
Go to Step 13
|
| 13 |
Does the sound signal work?
|
-
|
Go to Step 16
|
Go to Step 24
|
| 14 |
Does the sound signal work?
|
-
|
Go to Step 25
|
Go to Step 22
|
| 15 |
Does the sound signal work?
|
-
|
Go to Step 25
|
Go to Step 22
|
| 16 |
Eliminate increased resistance in the horn control circuit or horn ground circuit. Even resistance as low as 0.5 ohms can cause horn malfunction.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 17 |
Eliminate the open circuit or increased resistance in the positive battery voltage circuit on the horn relay winding.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 18 |
Important: The horn switch is part of the steering wheel air bag module. See. Section 8B, Supplemental Inflatable Restraint System (SIR).
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 19 |
Repair open or high resistance in the battery positive voltage circuit at the horn relay switch.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 20 |
Eliminate open circuit or high resistance in the horn control circuit.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 21 |
Eliminate open circuit or increased resistance in the ground circuit of the sound signal.
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 22 |
Important: Perform the BCM programming procedure when replacing the BCM. Replace the BCM. See. Section 9V, "Body Controller".
Is the renovation finished?
|
-
|
Go to Step 25
|
-
|
| 23 |
Replace the horn relay.
Is the replacement complete?
|
-
|
Go to Step 25
|
-
|
| 24 |
Replace the sound signal.
Is the replacement complete?
|
-
|
Go to Step 25
|
-
|
| 25 |
Sound the alarm.
Is the sound signal working properly?
|
-
|
-
|
Go to Step 1
|