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Circuit Test

  1. Under left side of instrument panel, remove trim panel, key cylinder pad and duct, as necessary, to access junction block No. 1 (this is the fuse/relay block). Remove set bolts and clamp securing junction block No. 1 in place. Separate tilt/telescopic ECU from junction block No. 1.
  2. Remove wiring harness clamp. Lower junction block No. 1. Disconnect larger of 2 electrical connectors from theft deterrent ECU, located above junction block No. 1. Place shift lever in Neutral (or depress clutch pedal). While holding ignition switch in START position, measure voltage between body ground and terminal ST of theft deterrent ECU connector (harness side). See Fig 1.
  3. 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 (clutch switch on M/T), or wiring harness.
Fig 1: Measuring Voltage At Theft Deterrent ECU (LS400)
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