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Test No. 1: Ecu Power Source Circuit: Testing

  1. Check WIPER (25-amp), ACC (15-amp), HORN HAZ (15-amp), MPX-B (15-amp) and ECU-IG (10-amp) fuses located in engine room and instrument panel junction block. If fuses are okay, go to next step. If fuses are open, locate and repair short circuit. See WIRING DIAGRAMS . Replace fuse.
  2. Turn ignition off. Disconnect body ECU harness connectors. Turn ignition on. Measure voltage between ground and terminals No. 9 and 10 of body ECU 15-pin harness connector R1. Voltage should be 10-14 volts. Turn ignition off. Measure voltage between ground and terminals No. 7 and 3 of body ECU 15-pin harness connector R1. Voltage should be 10-14 volts. Turn ignition on. Measure voltage between ground and terminal No. 9 (Gray wire) of body ECU 23-pin connector "A". Voltage should be 10-14 volts. If voltages are to specification, go to next step. If voltages are not to specification, go to next test listed. See appropriate TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING .
  3. Check continuity between ground and terminal No. 8 of body ECU 15-pin harness connector R1. If continuity is present, replace driver's side instrument panel junction block. If continuity is not present, repair or replace driver's side instrument panel junction block, wiring or connectors. See WIRING DIAGRAMS .
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