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Transponder Key Electronic Control Unit

  1. Transponder key Electronic Control Unit (ECU) individual component testing is not available from manufacturer. Transponder key ECU voltage may be checked. Ensure electrical connector is fully installed on transponder key ECU. Transponder key ECU is located behind instrument panel and contains a 12-pin electrical connector. See Figure.
  2. Turn ignition on. Using voltmeter, checking voltage between body ground and terminal No. 8 (Black/White) at transponder key ECU electrical connector. See Fig 1. Battery voltage should exist. Start engine while monitoring voltmeter. Voltmeter needle should swing strongly for about one second when engine is started. Turn ignition off. Remove voltmeter.
    Fig 1: Checking Voltage At Transponder Key Electronic Control Unit
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