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Test No. 2

NOTE: When ignition switch is in ACC position, battery voltage is applied to ACC terminal at instrument panel Electronic Control Unit (ECU). When ignition switch is in ON position, battery voltage is applied to SIG terminal at instrument panel ECU.

  1. Check ECU-IG & MIRR Fuse

    Remove ECU-IG and MIRR fuses from driver's side fuse/relay box located near driver's side kick panel. See Figure.
  2. Using ohmmeter, ensure continuity exists across each fuse. If each fuse is okay, go to next step. If any fuse is blown, check for short circuit in appropriate wiring circuit to the fuse and instrument panel ECU. See WIRING DIAGRAMS . Instrument panel ECU is located behind center of instrument panel and contains a 14-pin, 18-pin and 22-pin electrical connector. See Figure. Replace appropriate fuse and repair appropriate wiring as necessary.
  3. Check Voltage At Terminal No. 2 On Connector "C" (14-Pin Connector) & Terminal No. 21 On Connector "A" (22-Pin Connector) At Instrument Panel ECU Remove necessary components for access to instrument panel ECU. Instrument panel ECU is located behind center of instrument panel and contains a 14-pin, 18-pin and 22-pin electrical connector. See Figure.
  4. Ensure ignition is off. Disconnect electrical connectors at instrument panel ECU. Turn ignition on. Using voltmeter, check voltage between terminals No. 2 and 4 on connector "C" (14-pin connector) at instrument panel ECU. Using voltmeter, check voltage between terminal No. 21 on connector "A" (22-pin connector) and terminal No. 4 on connector "C" (14-pin connector) at instrument panel ECU.
  5. Voltage should be 10-14 volts. If voltage is not within specification, go to next step. If voltage is within specification, go to the next test listed. See appropriate TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING .

  6. Check Ground Circuit Wiring

    Check for defective connectors and Sky Blue wire between body ground and terminal No. 4 at connector "C" at instrument panel ECU. See WIRING DIAGRAMS . If no defective connectors or wire exists, and body ground is okay, go to next step. If connectors, wire or body ground are defective, repair as necessary.

  7. Check Power Circuit Wiring

    Check for defective connectors and wiring between battery, ignition switch, ECU-IG fuse, MIRR fuse and instrument panel ECU. See WIRING DIAGRAMS . If connectors or wires are defective, repair as necessary. If necessary to check ignition switch, see IGNITION SWITCH  under COMPONENT TESTS.
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