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SC300 & SC400

  1. Remove all necessary components to access theft deterrent ECU. See COMPONENT LOCATIONS  table. Disconnect electrical connectors from theft deterrent ECU. Ensure transmission is in Park.
  2. While holding ignition switch in START position, measure voltage between ground and Orange theft deterrent ECU 25-pin connector terminal No. 25 (Blue/Orange wire). See Fig 1. If 10-14 volts is measured, replace theft deterrent ECU. If 10-14 volts is not measured, check for faulty starter relay, park/neutral position switch, or wiring harness.
Fig 1: Measuring Voltage At Theft Deterrent ECU (SC300 & SC400)
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