THEFT DETERRENT SYSTEM TERMINALS OF ECU


  1. CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    B006H6ZN18

    1. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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    2. Reconnect the instrument panel junction block assembly connectors.

    3. Measure the resistance and voltage according to the value(s) in the table below.

      Tech Tips

      Measure the values on the wire harness side with the connector disconnected.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      MB-31 (BECU) - Body ground - Auxiliary battery power supply Power switch off 11 to 14 V
      MB-32 (IG) - Body ground - Ignition power supply (IG signal) Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      MB-30 (ACC) - Body ground - Ignition power supply (ACC signal) Power switch off Below 1 V
      Power switch on (ACC) 11 to 14 V
      MB-11 (GND1) - Body ground - Ground Always Below 1 Ω
      I18-6 (FLCY) - Body ground BR - Body ground Front door courtesy light switch assembly (for LH) input Front door LH closed 10 kΩ or higher
      Front door LH open Below 1 Ω
      I18-27 (FRCY) - Body ground L - Body ground Front door courtesy light switch assembly (for RH) input Front door RH closed 10 kΩ or higher
      Front door RH open Below 1 Ω
      MB-13 (LCTY) - Body ground - Rear door courtesy light switch assembly (for LH) input Rear door LH closed 10 kΩ or higher
      Rear door LH open Below 1 Ω
      MB-2 (RCTY) - Body ground - Rear door courtesy light switch assembly (for RH) input Rear door RH closed 10 kΩ or higher
      Rear door RH open Below 1 Ω
      MB-4 (BCTY) - Body ground - Back door courtesy light switch input Back door closed 10 kΩ or higher
      Back door open Below 1 Ω
      I18-11 (HCTY) - Body ground B - Body ground Engine hood courtesy switch input Engine hood open 10 kΩ or higher
      Engine hood closed Below 1 Ω

    4. Install the main body ECU (multiplex network body ECU) to instrument panel junction block assembly.

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    5. Measure the voltage and check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      3D-13 (LSFL) - Body ground GR - Body ground Front door LH unlock detection switch input Front door LH unlocked Below 1 V
      Front door LH locked Pulse generation
      3D-12 (LSFR) - Body ground V - Body ground Front door RH unlock detection switch input Front door RH unlocked Below 1 V
      Front door RH locked Pulse generation
      I18-29 (L2) - Body ground V - Body ground Driver door key-linked lock input Driver door key cylinder turned to lock position Below 1 V
      Driver door key cylinder off Pulse generation
      I18-2 (UL3) - Body ground G - Body ground Driver door key-linked unlock input Driver door key cylinder turned to unlock position Below 1 V
      Driver door key cylinder off Pulse generation
      3D-14 (LSR) - Body ground LG - Body ground Rear door LH unlock detection switch input Rear door LH or RH unlocked Below 1 V
      Rear door LH and RH locked Pulse generation
      3D-14 (LSR) - Body ground LG - Body ground Rear door RH unlock detection switch input Rear door RH or LH unlocked Below 1 V
      Rear door RH and LH locked Pulse generation
      I19-12 (ISIF) - Body ground* P - Body ground Intrusion sensor (theft warning ultrasonic sensor) signal input No moving object detected by sensor 11 to 14 V
      Theft deterrent system changed from disarmed state to arming preparation state

      Pulse generation

      (See waveform)
      I18-7 (GPBS) - Body ground* GR - Body ground Glass breakage sensor signal input Glass breakage sensor circuit not open Below 1 V
      I19-18 (SSCL) - Body ground W - Body ground Theft warning siren assembly drive

      Theft warning siren assembly sounding

      (Theft deterrent system in alarm sounding state)

      Pulse generation

      (Below 1 V ← → 11 to 14 V)
      3F-27 (HORN) - Body ground SB - Body ground Vehicle horns drive

      Vehicle horns sounding

      (Theft deterrent system in alarm sounding state)

      Pulse generation

      (Below 1 V ← → 11 to 14 V)

      • *: w/ Intrusion Sensor

    6. Using an oscilloscope, check the waveform.

      Tech Tips

      The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.


      1. Waveform (Reference)

        A003NUZC03
        *a IOUT Initial Signal *b IOUT Initial Response
        *c Approximately 1.0 Second *d Initial Diagnosis
        *e Approximately 1.0 to 1.6 Seconds *f Approximately 0.05 Seconds
        *g Approximately 5.5 Seconds *h Disarmed State
        *i Arming Preparation State - -