Test No. 4
NOTE:
Test procedure is based on assumption that standard horns operate properly using horn pad on steering wheel, but will not operate with anti-theft system.
- Check Voltage At Terminal No. 12 At Anti-Theft System Electronic Control Unit (ECU)
Remove glove compartment door for access to anti-theft system ECU. Anti-theft system ECU is located near passenger's side of instrument panel, behind glove box, just above kick panel and uses a 12-pin electrical connector and a 22-pin electrical connector. See Figure. - Ensure ignition is off. Disconnect electrical connectors at anti-theft system ECU. Using voltmeter, check voltage between ground and terminal No. 12 (Green/Black wire). See Fig 1. This is the Green/Black wire between horn relay and anti-theft system ECU. See WIRING DIAGRAMS .
- Voltage should be 10-14 volts. If voltage is not within specification, go to next step. If voltage is within specification, replace anti-theft system ECU. See ANTI-THEFT SYSTEM ECU under REMOVAL & INSTALLATION.
- Check for defective connectors and Green/Black wire between 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 connectors or wiring as necessary. If necessary to check horn relay, see HORN RELAY under COMPONENT TESTS.