FRONT POWER SEAT CONTROL SYSTEM(w/ Memory) TERMINALS OF ECU


  1. CHECK FRONT POWER SEAT SWITCH LH (for LHD)


    1. Disconnect the a9 and a10 front power seat switch LH connectors.

      A01MFO8E01

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

      Tech Tips

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      a9-2 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      a9-7 (+B) - a9-2 (GND) W - W-B Auxiliary battery power supply Power switch off 11 to 14 V
      a10-12 (SYSB) - a9-2 (GND) P - W-B Auxiliary battery power supply Power switch off 11 to 14 V
      a10-3 (IG) - a9-2 (GND) P - W-B Ignition power supply Power switch on (IG) 11 to 14 V
      a10-3 (IG) - a9-2 (GND) P - W-B Ignition power supply Power switch off Below 1 V
      a10-10 (DBCL) - Body ground GR - Body ground Driver seat belt buckle switch signal Driver seat belt fastened Below 1 Ω
      a10-10 (DBCL) - Body ground GR - Body ground Driver seat belt buckle switch signal Driver seat belt unfastened 10 kΩ or higher

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the a9 and a10 front power seat switch LH connectors.

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      a9-6 (+B2) - a9-2 (GND) SB - W-B Lumbar support adjuster power source Power switch off 11 to 14 V
      a9-1 (GND2) - Body ground W-B - Body ground Lumbar support adjuster ground Always Below 1 Ω
      a9-3 (SLD+) - a9-2 (GND) L - W-B Slide motor signal (forward) Slide switch off Below 1 V
      Slide switch on (Forward) 11 to 14 V
      a9-4 (SLD-) - a9-2 (GND) GR - W-B Slide motor signal (rearward) Slide switch off Below 1 V
      Slide switch on (Rearward) 11 to 14 V
      a9-5 (FRV-) - a9-2 (GND) V - W-B Front vertical motor signal (downward) Front vertical switch off Below 1 V
      Front vertical switch on (Downward) 11 to 14 V
      a9-8 (FRV+) - a9-2 (GND) B - W-B Front vertical motor signal (upward) Front vertical switch off Below 1 V
      Front vertical switch on (Upward) 11 to 14 V
      a9-9 (RCL+) - a9-2 (GND) P - W-B Reclining motor signal (forward) Reclining switch off Below 1 V
      Reclining switch on (Forward) 11 to 14 V
      a9-11 (RCL-) - a9-2 (GND) LG - W-B Reclining motor signal (rearward) Reclining switch off Below 1 V
      Reclining switch on (Rearward) 11 to 14 V
      a9-10 (LFT+) - a9-2 (GND) V - W-B Lifter motor signal (upward) Lifter switch off Below 1 V
      Lifter switch on (Upward) 11 to 14 V
      a9-12 (LFT-) - a9-2 (GND) G - W-B Lifter motor signal (downward) Lifter switch off Below 1 V
      Lifter switch on (Downward) 11 to 14 V
      a10-1 (SGND) - a9-2 (GND) BR - W-B Position sensor ground Always Below 1 Ω
      a10-5 (SSRS) - a10-1 (SGND) G- BR Slide position signal Slide function operating 4.8 to 5.1 V

      If the result is not as specified, the front power seat switch LH may be malfunctioning.

  2. CHECK FRONT POWER SEAT SWITCH RH (for RHD)


    1. Disconnect the a9 and a10 front power seat switch RH connectors.

      A01MFO8E02

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

      Tech Tips

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      Z4-2 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      Z4-7 (+B) - Z4-2 (GND) W - W-B Auxiliary battery power supply Power switch off 11 to 14 V
      Z5-12 (SYSB) - Z4-2 (GND) P - W-B Auxiliary battery power supply Power switch off 11 to 14 V
      Z5-3 (IG) - Z4-2 (GND) P - W-B Ignition power supply Power switch on (IG) 11 to 14 V
      Z5-3 (IG) - Z4-2 (GND) P - W-B Ignition power supply Power switch off Below 1 V
      Z5-10 (DBCL) - Body ground GR - Body ground Driver seat belt buckle switch signal Driver seat belt fastened Below 1 Ω
      Z5-10 (DBCL) - Body ground GR - Body ground Driver seat belt buckle switch signal Driver seat belt unfastened 10 kΩ or higher

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the Z4 and Z5 front power seat switch RH connectors.

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      Z4-6 (+B2) - Z4-2 (GND) SB - W-B Lumbar support adjuster power source Power switch off 11 to 14 V
      Z4-1 (GND2) - Body ground W-B - Body ground Lumbar support adjuster ground Always Below 1 Ω
      Z4-3 (SLD+) - Z4-2 (GND) L - W-B Slide motor signal (forward) Slide switch off Below 1 V
      Slide switch on (Forward) 11 to 14 V
      Z4-4 (SLD-) - Z4-2 (GND) GR - W-B Slide motor signal (rearward) Slide switch off Below 1 V
      Slide switch on (Rearward) 11 to 14 V
      Z4-5 (FRV-) - Z4-2 (GND) V - W-B Front vertical motor signal (downward) Front vertical switch off Below 1 V
      Front vertical switch on (Downward) 11 to 14 V
      Z4-8 (FRV+) - Z4-2 (GND) B - W-B Front vertical motor signal (upward) Front vertical switch off Below 1 V
      Front vertical switch on (Upward) 11 to 14 V
      Z4-9 (RCL+) - Z4-2 (GND) P - W-B Reclining motor signal (forward) Reclining switch off Below 1 V
      Reclining switch on (Forward) 11 to 14 V
      Z4-11 (RCL-) - Z4-2 (GND) LG - W-B Reclining motor signal (rearward) Reclining switch off Below 1 V
      Reclining switch on (Rearward) 11 to 14 V
      Z4-10 (LFT+) - Z4-2 (GND) V - W-B Lifter motor signal (upward) Lifter switch off Below 1 V
      Lifter switch on (Upward) 11 to 14 V
      Z4-12 (LFT-) - Z4-2 (GND) G - W-B Lifter motor signal (downward) Lifter switch off Below 1 V
      Lifter switch on (Downward) 11 to 14 V
      Z5-1 (SGND) - Z4-2 (GND) BR - W-B Position sensor ground Always Below 1 Ω
      Z5-5 (SSRS) - Z5-1 (SGND) G- BR Slide position signal Slide function operating 4.8 to 5.1 V

      If the result is not as specified, the front power seat switch RH may be malfunctioning.

  3. CHECK OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR) (for LHD)

    A01MJH9E14

    1. Disconnect the L10 outer mirror control ECU assembly (driver door) connector.

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

      Tech Tips

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L10-6 (CPUB) - L10-7 (GND) BR- BR Auxiliary battery power supply Power switch off 11 to 14 V
      L10-14 (BDR) - L10-7 (GND) SB - BR Auxiliary battery power supply Power switch off 11 to 14 V
      L10-5 (SIG) - L10-7 (GND) Y - BR Ignition power supply Power switch on (IG) 11 to 14 V
      L10-5 (SIG) - L10-7 (GND) Y - BR Ignition power supply Power switch off Below 1 V
      L10-7 (GND) - Body ground BR - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness.

    3. Reconnect the L10 outer mirror control ECU assembly (driver door) connector.

    4. Measure the voltage according to the value(s) in the table below.

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L10-1 (MM) - L10-7 (GND) LG - BR SET switch signal for seat memory switch LH SET switch on Below 1 V
      SET switch off 11 to 14 V
      L10-2 (M1) - L10-7 (GND) BE - BR M1 switch signal for seat memory switch LH M1 switch on Below 1 V
      M1 switch off 11 to 14 V
      L10-3 (M2) - L10-7 (GND) GR - BR M2 switch signal for seat memory switch LH M2 switch on Below 1 V
      M2 switch off 11 to 14 V

      If the result is not as specified, the outer mirror control ECU assembly (driver door) may be malfunctioning.

  4. CHECK OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR) (for RHD)

    A01MJH9E18

    1. Disconnect the L1 outer mirror control ECU assembly (driver door) connector.

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

      Tech Tips

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L1-6 (CPUB) - L1-7 (GND) GR - BR Auxiliary battery power supply Power switch off 11 to 14 V
      L1-14 (BDR) - L1-7 (GND) R - BR Auxiliary battery power supply Power switch off 11 to 14 V
      L1-5 (SIG) - L1-7 (GND) G - BR Ignition power supply Power switch on (IG) 11 to 14 V
      L1-5 (SIG) - L1-7 (GND) G - BR Ignition power supply Power switch off Below 1 V
      L1-7 (GND) - Body ground BR - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness.

    3. Reconnect the L1 outer mirror control ECU assembly (driver door) connector.

    4. Measure the voltage according to the value(s) in the table below.

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L1-1 (MM) - L1-7 (GND) SB - BR SET switch signal for seat memory switch RH SET switch on Below 1 V
      SET switch off 11 to 14 V
      L1-2 (M1) - L1-7 (GND) P - BR M1 switch signal for seat memory switch RH M1 switch on Below 1 V
      M1 switch off 11 to 14 V
      L1-3 (M2) - L1-7 (GND) L - BR M2 switch signal for seat memory switch RH M2 switch on Below 1 V
      M2 switch off 11 to 14 V

      If the result is not as specified, the outer mirror control ECU assembly (driver door) may be malfunctioning.

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


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

      for LHD: Click here

      for RHD: Click here

      A01MGUIC31
      *1 Main Body ECU (Multiplex Network Body ECU) - -

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

      Tech Tips

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

      Tester Connection 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 Power switch on (IG) 11 to 14 V
      MB-32 (IG) - Body ground - Ignition power supply Power switch off Below 1 V
      MB-30 (ACC) - Body ground - Ignition power supply Power switch on (ACC) 11 to 14 V
      MB-30 (ACC) - Body ground - Ignition power supply Power switch off Below 1 V
      MB-11 (GND1) - Body ground - Ground Always Below 1 Ω
      G6-6 (FLCY) - Body ground P - Body ground Front door courtesy light switch assembly (driver door) input Front door LH closed (OFF) → open (ON) 10 kΩ or higher → Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness.