LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2007 >> RX 400h AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 307 (Brake Control System) >> Vehicle Stability Control System >> DTC C1242/42 IG2 Power Source Circuit >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota FJ Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: When replacing the master cylinder solenoid, perform zero point calibration (See CALIBRATION  ).
  1. CHECK BATTERY VOLTAGE 
    1. Check the battery voltage.

      Standard voltage: 

      11 to 14 V 

    NG: CHECK CHARGING SYSTEM  (See ON-VEHICLE INSPECTION )

    OK: Go to next step 

  2. CHECK SKID CONTROL ECU TERMINAL VOLTAGE (IG2) 
    1. Disconnect the skid control ECU A5 connector.
    2. Fig 1: Identifying Skid Control ECU A5 Connector
      G05112283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      A5-1 (IG2) - A5-4 (GND3) 11 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT FUSE (IGN) 
    1. Remove the IGN fuse from the driver side J/B.
    2. Fig 2: Identifying IGN Fuse
      G05112284Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (GND TERMINAL CONTINUITY) 
    1. Confirm that the skid control ECU connector and speed sensor connector are properly connected.
    2. Disconnect the skid control ECU connectors.
    3. Fig 3: Identifying Skid Control ECU A4 And A5 Connectors
      G05112282Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Inspect both the connector case and the terminal for deformation and corrosion.

      OK: 

      No deformation or corrosion. 

    5. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-1 (GND1) - Body ground Below 1 Ω
      A4-32 (GND2) - Body ground Below 1 Ω
      A5-4 (GND3) - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK/CLEAR  ).
    2. Drive the vehicle at a speed of 2 mph (3 km/h) or more for 7 seconds or more.
    3. Check if the same DTC is output (See DTC CHECK/CLEAR  ).

    B: END 

    A: REPLACE MASTER CYLINDER SOLENOID  (See DISASSEMBLY )