Test No. 3
- Check Anti-Theft System Horn
Check anti-theft system horn operation. See ANTI-THEFT SYSTEM HORN under COMPONENT TESTS. If anti-theft system horn operates, go to next step. Replace anti-theft system horn if horn fails to operate.
- Check Voltage At Terminal No. 9 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.
- Turn ignition off. Disconnect harness connectors at anti-theft system ECU. Check voltage between ground and terminal No. 9 (Green/Yellow wire) at 12-pin harness connector at anti-theft ECU. See Fig 1. See WIRING DIAGRAMS . If battery voltage exists, go to next step. If voltage does not exist, go to step 5.
- Check and repair damaged harness connectors and Green/White wire at HAZ-TRN fuse, then changes to Sky Blue wire and finally Green/Yellow wire at anti-theft system ECU. See WIRING DIAGRAMS . HAZ-TRN fuse is located in engine compartment fuse/relay box near battery. See Figure.
- Check Anti-Theft System Horn Wiring
Check for damaged harness connectors and White wire between anti-theft system horn and terminal No. 2 on anti-theft system ECU. See WIRING DIAGRAMS . See Fig 1. If harness connectors and wiring are okay, replace anti-theft system ECU. See ANTI-THEFT SYSTEM ECU under REMOVAL & INSTALLATION. If harness connectors or wiring are defective, repair as necessary.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002