Ignition Switch Circuit

Check CIG and ECU-IG fuses in instrument panel junction box. If fuse(s) is bad, repair short in circuit and replace fuse(s). See WIRING DIAGRAMS. Disconnect ECU connectors. Turn ignition on. Using voltmeter connected to ground, backprobe ECU 22-pin connector T4 terminal No. 13 (Black/Red wire). See Figure. If voltage readings are not 10-14 volts, repair wiring between ECU and battery. See WIRING DIAGRAMS . If voltage reading is 10-14 volts, check ECU. See PIN VOLTAGE TESTS . If pin voltages are not within specification, replace ECU and retest system operation.