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Test No. 1

NOTE: Test No. 1 is used to check the power supply to the instrument panel Electronic Control Unit (ECU).

  1. ECU-B Fuse

    Remove ECU-B fuse from driver's side fuse/relay box located near driver's side kick panel. See Figure.
  2. Using ohmmeter, ensure continuity exists across fuse. If fuse is okay, go to next step. If fuse is blown, check for short circuit in 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 fuse and repair wiring as necessary.
  3. Check Voltage Between Terminals No. 1 & 4 At Connector "C" (14-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. Using voltmeter, check voltage between terminals No. 1 and 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, ECU-B fuse and terminal No. 1 at instrument panel ECU. See WIRING DIAGRAMS . If connectors or wire are defective, repair as necessary.
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