Sound signal
Caution: Always lock the passive restraint system when working in the immediate vicinity of its components to prevent the possibility of accidental deployment of the airbags, which could result in serious injury (see paragraph 26).
Examination
Note: Before troubleshooting an electrical circuit, check the integrity of the relevant fuses.
1. Disconnect the wiring connector from the horn.
2. To test the sound signal, apply power voltage to the signal output directly from the battery through the cigarette lighter wire. If there is no sound, replace the signal.
3. If the sound signal does not work, check for voltage at its output while the sound signal button is pressed. If there is voltage, check the horn connection to ground.
4. If there is no voltage, check the horn power relay (see paragraph 5).
5. If the relay is normal, check the voltage in the control and actuator contact circuits. If there is no voltage in any of these circuits, check the continuity of the wires between the relay and the fuse panel.
6. If there is voltage in both relay circuits, press the horn button and check the section of the circuit between the relay and the button by connecting it to ground. If the device does not show a ground connection, check the circuit section for an open. If no break is found, replace the horn button.
7. If the device shows a ground connection through the horn button, check the circuit section between the horn and the relay for an open or short circuit.
Removal
8. To access the sound signals, remove the front bumper panel (see chapter 11).
9. To remove the horn(s), disconnect the wiring connector and unscrew the horn bracket mounting bolt (see Figure 18.9).
Figure 18.9. Location of sound signal mounting bolts.
Installation
10. Install the horn in the reverse order of removal.
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