FixVault

Anti-Theft Horn Circuit

NOTE: If LEXUS scan tool is available, start test from step 1). If this scan tool is not available, start test from step 2).

  1. Check Anti-Theft Horn Using Scan Tool

    Connect a jumper wire between DLC1 connector terminals E1 and Tc. See Figure. Using scan tool, operate anti-theft horn in ACTIVE TEST. If anti-theft horn does not operate, go to next step. If anti-theft horn operates, go to next test listed in appropriate TROUBLE SHOOTING SYMPTOMS table.
  2. Check Anti-Theft Horn

    Check anti-theft horn. See ANTI-THEFT HORN under COMPONENT TESTS. If anti-theft horn is okay, go to next step. Replace anti-theft horn as necessary. Retest system operation.
  3. Check Circuits

    Check circuits for faults between anti-theft horn and body control ECU. See WIRING DIAGRAMS. Repair or replace as necessary. If circuits are okay, go to next test listed in appropriate TROUBLE SHOOTING SYMPTOMS table.