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Power Source Circuit

  1. Check MPX-1 and IG2 fuses. Replace fuses as necessary. If fuses are okay, go to next step.
  2. Turn ignition on. Measure voltage (backprobe) between transponder key ECU terminals No. 2 (Black wire) and No. 14 (White/Black wire). See Figure. About 10-14 volts should be present. Turn ignition off. Disconnect transponder key ECU connector. Measure voltage between transponder key ECU connector terminal No. 1 (Violet/Yellow wire) and No. 14 (White/Black wire). About 10-14 volts should be present. If voltages are not to specification, go to next step. If voltages are to specification, check next component listed in TROUBLE SHOOTING SYMPTOMS  table.
  3. Check wiring and connectors between transponder key ECU and ground. Repair or replace wiring as necessary. If wiring is okay, check next component listed in TROUBLE SHOOTING SYMPTOMS  table.
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