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Home >> Acura >> 2017 >> MDX Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Security System / Keyless Entry System - Symptom Troubleshooting (Except Hybrid) >> Keyless/Power Door Locks/Security System Symptom Troubleshooting >> The Horn Does Not Sound And/Or The Headlights Do Not Flash When The Panic Button On The Remote Is Pressed
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The Horn Does Not Sound And/Or The Headlights Do Not Flash When The Panic Button On The Remote Is Pressed

NOTE: Before troubleshooting, check the B-CAN DTCs. If any DTC is indicated, troubleshoot the indicated DTC first.
  1. Panic check

    -1. Press the PANIC button.

    Do the horns sound and the lights flash?

    YES 

    Intermittent failure, the system is OK at this time.

    NO: Horns

    Go to step 2.

    NO: Lights

    Go to step 3.

  2. Horn operation check

    -1. Press the horn button.

    Do the horns sound?

    YES 

    Go to step 4.

    NO 

    Check the horn circuit.

  3. Headlight operation check

    -1. Turn the headlight switch ON.

    Do the headlights come on?

    YES 

    Go to step 4.

    NO 

    Check the lighting circuit.

  4. Keyless remote check

    -1. Test the keyless remote.

    The keyless remote is OK?

    YES 

    Replace the MICU - Refer to: Driver's Under-Dash Fuse/Relay Box Removal and Installation, or Passenger's Under-Dash Fuse/Relay Box Removal and Installation .

    NO 

    Replace the keyless remote, then register the new transmitter - Refer to: Keyless Access System Registration (2014 2015), or Keyless Access System Registration (2016) .