Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Check Security Horn Operation
- CHECK SECURITY HORN CHIRP OPERATION
With CONSULT-II
- Check security horn chirp "HORN" in "ACTIVE TEST" mode with CONSULT-II.
- Perform operation shown on display.
Security horn should sound.
Without CONSULT-II
- Disconnect BCM connector.
- Apply ground to BCM connector E204 terminal 127 (P/L).
Security horn should sound.
OK or NG
- OK: Security horn alarm is OK.
- NG: GO TO 2.
- CHECK SECURITY HORN RELAY
Check security horn relay condition.
OK or NG
- OK: GO TO 3.
- NG: Replace security horn relay.
- CHECK POWER SUPPLY FOR SECURITY HORN RELAY
- Disconnect security horn relay connector.
- Check voltage between security horn relay connector E77 terminal 2 (Y/B) and ground.
2 (Y/B) - Ground: Battery voltage
OK or NG
- OK: GO TO 4.
- NG: Check the following.
- 10A fuse [No. 78, located in the fuse, fusible link and relay block (J/B)]
- Harness for open or short between security horn relay and fuse.
- CHECK SECURITY HORN RELAY CIRCUIT
- Disconnect BCM and security horn relay connector.
- Check continuity between BCM connector E204 terminal 127 (P/L) and security horn relay connector E77 terminal 1 (P/L).
127 (p/L) - 1 (P/L) :Continuity should exist.
OK or NG
- OK: GO TO 5.
- NG: Repair or replace harness.
- CHECK SECURITY HORN RELAY CIRCUIT
- Disconnect security horn relay and security horn connector.
- Check continuity between security horn relay connector E77 terminal 3 (P/B) and security horn connector E30 terminal 1 (P/B).
3 (P/B) - 1 (P/B) :Continuity should exist.
OK or NG
- OK: Replace security horn.
- NG: Repair or replace harness.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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