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Test No. 4

NOTE: Test procedure is based on the assumption that standard horns operate properly using horn pad on steering wheel, but will not operate with anti-theft system.

  1. Check Voltage At Terminal No. 12 At Anti-Theft System Electronic Control Unit (ECU)

    Access anti-theft system ECU. Anti-theft system ECU is located behind glove box and uses a 12-pin and a 22-pin harness connector. See Figure.
  2. Turn ignition off. Disconnect harness connectors at anti-theft system ECU. Check voltage between ground and terminal No. 12 (Green/Orange wire). See Fig 1. See WIRING DIAGRAMS .
  3. If battery voltage does not exist, go to next step. If voltage exists, replace anti-theft system ECU. See ANTI-THEFT SYSTEM ECU  under REMOVAL & INSTALLATION.
  4. Check for damaged harness connectors and Green/Orange wire between horn relay changing to Sky Blue and back to Green/Orange wire to anti-theft system ECU and horn relay. See WIRING DIAGRAMS . Horn relay is located in engine compartment fuse/relay box near battery. See Figure. Repair harness connectors or wiring as necessary. To check horn relay, see HORN RELAY  under COMPONENT TESTS.
Fig 1: Checking Voltage At Terminal No. 12 At Anti-Theft System ECU
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