LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2007 >> ES 350 >> Repair and Diagnosis >> Accessories & Equipment >> Cruise Control Systems >> Cruise Control >> Dynamic Radar Cruise Control System >> Millimeter Wave Radar Sensor Power Source Circuit >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

NOTE:
  • When the distance control ECU and/or ECM are replaced with a new one, initialization must be performed (See INSTALLATION  ).
  • When the millimeter wave radar sensor is replaced with a new one, adjustment of the radar sensor beam axis must be performed (See ADJUSTMENT  ).
  1. CHECK DISTANCE CONTROL ECU (IGB VOLTAGE) 
    1. Disconnect the A31 sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A31-5 (IGB) -Body ground Engine switch on (IG) 10 to 14 V
    Fig 1: Identifying A31 Connector Terminals
    G05252222Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  3

    OK: Go to Next Step 

  2. CHECK WIRE HARNESS (MILLIMETER WAVE RADAR SENSOR - ECM AND BODY GROUND) 
    1. Disconnect the A31 sensor connector.
    2. Disconnect the A10 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A10-38 (LGND) -A31-1 (LGND) Always Below 1 Ω
      A31-1 (LGND)-Body ground Always 10 kΩ or higher
      A31-2 (SGND) - Body ground Always Below 1Ω
    Fig 2: Identifying A31 And A10 Connectors Terminals
    G05252223Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  3. CHECK WIRE HARNESS (MILLIMETER WAVE RADAR SENSOR - DISTANCE CONTROL ECU) 
    1. Disconnect the A31 sensor connector.
    2. Disconnect the A8 ECU connector.
    3. Measure the resistance according to the value(s) in the table below

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A31-5 (IGB) - A8-13 (IGB) Always Below 1 Ω
      A8-13 (IGB) - Body ground Always 10 kΩ or higher
    Fig 3: Identifying A31 And A8 Connectors Terminals
    G05252224Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE DISTANCE CONTROL ECU (See  REMOVAL   )