LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2007 >> IS 250 AWD >> Repair and Diagnosis >> Brakes >> Traction Control >> Brake Control >> VEHICLE STABILITY CONTROL SYSTEM (w/ VDIM) >> Test Mode Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test Mode Procedure

  1. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK 
    1. Release the parking brake.
      NOTE: Before releasing the parking brake, move the shift lever to the P position for safety.

      HINT:

      When the parking brake is applied or the level of the brake fluid is low, the BRAKE warning light comes on.

      Fig 1: Identifying ABS, Brake Warning Lights, And Master Caution, Slip Indicator Lights
      G05319279Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When the engine switch is turned on (IG), check that the ABS, BRAKE warning lights, and master caution, SLIP indicator lights illuminate and turn off after the engine starts. Make sure that the message on the multi-information display changes from "CHECK" to "COMPLETE" for 2 seconds.

      HINT:

      If the ECU stores any DTCs, the ABS, BRAKE, VSC warning (multi-information display and master caution indicator light) lights, and SLIP indicator light come on.

      If the indicator remains on or does not come on, proceed to troubleshooting for the light circuits listed below.

      LIGHT CIRCUITS TROUBLESHOOTING CHART

      Trouble Area See procedure
      ABS warning light circuit ABS WARNING LIGHT REMAINS ON  or ABS WARNING LIGHT DOES NOT COME ON 
      BRAKE warning light circuit BRAKE WARNING LIGHT REMAINS ON  or BRAKE WARNING LIGHT DOES NOT COME ON 
      VSC warning light circuit VSC WARNING LIGHT REMAINS ON  or VSC WARNING LIGHT DOES NOT COME ON 
      SLIP indicator light circuit SLIP INDICATOR LIGHT REMAINS ON  or SLIP INDICATOR LIGHT DOES NOT COME ON 
  2. SENSOR SIGNAL CHECK BY TEST MODE (SIGNAL CHECK) (WHEN USING INTELLIGENT TESTER:) 
    NOTE: After replacement of the skid control ECU and/or yaw rate and acceleration sensor, perform zero point calibration of the yaw rate and acceleration sensor.

    HINT:

    • If the engine switch is turned from on (IG) to on (ACC) or off during Test Mode (signal check), DTCs of the signal check function will be erased.
    • During Test Mode (signal check), the skid control ECU records all DTCs of the signal check function. By performing the Test Mode (signal check), the codes are erased if a normal condition is confirmed. The remaining codes are the codes where an abnormality was found.
    1. Procedure for Test Mode.
      1. Turn the engine switch off.
      2. Connect the intelligent tester to the DLC3.
      3. Check that the steering wheel is centered and move the shift lever to the P position.
      4. Turn the engine switch on (IG).
        Fig 2: Identifying Intelligent Tester To DLC3
        G05319280Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Set the intelligent tester to Test Mode (select "SIGNAL CHECK").

        HINT:

        Refer to the intelligent tester operator's manual for further details.

        Fig 3: CONSULT-II Display - SIGNAL CHECK
        G05319281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Check that the ABS warning light, and master caution indicator light blink and "VSC TEST MODE" is displayed on the multi-information display (Test Mode).

        HINT:

        If the ABS and VSC warning (multi-information display and master caution indicator light) lights do not blink, inspect the TS and CG terminal circuit, and ABS and VSC warning light circuits.

        TROUBLESHOOTING CHART

        Trouble Area See procedure
        TS and CG terminal circuit TS AND CG TERMINAL CIRCUIT 
        ABS warning light circuit ABS WARNING LIGHT DOES NOT COME ON 
        VSC warning light circuit VSC WARNING LIGHT DOES NOT COME ON 
        Fig 4: Identifying Indicator Light Blinking Pattern And VSC TEST MODE Display
        G05319282Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      7. Check the ABS sensor.

        HINT:

        Check that the ABS warning light is blinking in Test Mode and perform the check.

        Fig 5: ABS Warning Light Blinking Pattern In Test Mode
        G05319283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. LOST BOOSTER PRESSURE JUDGMENT CHECK AND MASTER CYLINDER PRESSURE SENSOR ZERO POINT CALIBRATION (WHEN USING INTELLIGENT TESTER:) 
    NOTE: Preform the check in the lost booster pressure state (negative pressure in the booster is depressurized).
    1. Turn the engine switch on (IG).
    2. Check that the BRAKE warning light comes on when depressing the brake pedal with a force of 59 N (6 kgf, 13.2 lbf) or more for 1 second or more. (The lost booster pressure state is judged normal.)
    3. Start the engine depressing the brake pedal with a force of 59 N (6 kgf, 13.2 lbf) or more for 1 second or more.
    4. Check that the BRAKE warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged normal.)
    5. Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)
      NOTE:
      • If you slowly depress the brake pedal or depress it again, master cylinder pressure sensor zero point calibration is not performed normally.
      • If lost booster pressure judgment check is not completed normally, master cylinder pressure sensor check is not judged.
      • If recheck is performed after the engine has started, end the Test Mode, transit to the Test Mode again, and release the vacuum in the booster by pumping the brake pedal prior to the recheck.
  4. ACCELERATION SENSOR CHECK (WHEN USING INTELLIGENT TESTER:) 
    1. Keep the vehicle stationary on a level surface for 1 second or more.

      HINT:

      The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

  5. MASTER CYLINDER PRESSURE SENSOR CHECK (WHEN USING INTELLIGENT TESTER:) 
    1. Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, and quickly and continuously depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second.
    2. Check that the ABS warning light stays on for 3 seconds.

      HINT:

      • Ensure that the ABS warning light come on.
      • While the ABS warning light stays on, continue to depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more.
      • The ABS warning light comes on for 3 seconds every time brake pedal operation above is performed.
      • If the check of the master cylinder pressure sensor is not completed, depressing the brake pedal causes further decrease in the negative pressure, making the sensor check difficult to be completed.
      • If the negative pressure is insufficient, the master cylinder pressure sensor check may not be completed. In this case, run the engine at idle to obtain sufficient negative pressure.
      • If the brake pedal is strongly depressed when the negative pressure is insufficient, the BRAKE warning light may come on in accordance with the booster pressure control. In this case, run the engine at idle to obtain sufficient negative pressure.
  6. SPEED SENSOR CHECK (WHEN USING INTELLIGENT TESTER:) 
    1. Check the reverse signal.
      1. Drive the vehicle in reverse for more than 1 second at 2 mph (3 km/h) or more.

        HINT:

        Drive the vehicle in reverse and check the speed sensor signal. The sensor check cannot be completed if the vehicle speed is 28 mph (45 km/h) or more.

    2. Check the forward signal.
      1. Drive the vehicle straight ahead.

        Accelerate the vehicle to a speed of 28 mph (45 km/h) or more for several seconds and check that the ABS warning light goes off.

        HINT:

        The sensor check may not be completed if the vehicle has its wheels spun.

    3. Stop the vehicle.
      NOTE:
      • Before performing the speed sensor check, complete the acceleration sensor and master cylinder pressure sensor checks.
      • The speed sensor check may not be completed if the speed sensor check is started while turning the steering wheel or spinning the wheels.
      • After the ABS warning light goes off and if the vehicle speed exceeds 50 mph (80 km/h), a signal check code will be stored again. Accelerate or stop the vehicle before the speed reaches 50 mph (80 km/h).
      • If the signal check has not been completed, the ABS warning light blinks while driving and the ABS system does not operate.
      • If the vehicle is driven in reverse at 28 mph (45 km/h) or more, the sensor check will not be completed.

      HINT:

      When the sensor check has been completed, the ABS warning light goes off while driving and blinks in the Test Mode pattern while stationary.

    4. Check the VSC sensor.

      Check that the master caution indicator light blinks and "VSC TEST MODE" is displayed on the multi-information display, and perform the check.

      Fig 6: Identifying Indicator Light Blinking Pattern And VSC TEST MODE Display
      G05319284Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. YAW RATE SENSOR CHECK (WHEN USING INTELLIGENT TESTER:) 
    1. Check the output of the yaw rate sensor.
      1. Keep the vehicle in a stationary condition on a level surface for 1 second or more.
      2. Move the shift lever from the P to the D position and drive the vehicle at a speed of approximately 3 mph (5 km/h), and turn the steering wheel either to the left or right 90° or more until the vehicle makes a 180° turn.
      3. Stop the vehicle and move the shift lever to the P position. Check that the skid control buzzer sounds for 3 seconds.
        Fig 7: Identifying Vehicle Start And Stop Position
        G05319285Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        • If the skid control buzzer sounds, the sensor check is completed normally.
        • If the skid control buzzer does not sound, check the skid control buzzer circuit (See SKID CONTROL BUZZER CIRCUIT  ), then perform the sensor check again.
        • If the skid control buzzer still does not sound, there is a malfunction in the yaw rate sensor, so check the DTC.
        • At the end of the 180° turn, the direction of the vehicle should be within 175° to 185° of its start position.
        • Do not spin the wheels.
        • Do not turn the engine switch off while turning.
        • Do not move the shift lever to the P position while turning, but changing in the vehicle speed, stopping, or driving in reverse is possible.
        • Complete the turn within 20 seconds.
  8. END OF SENSOR CHECK (WHEN USING INTELLIGENT TESTER:) 
    1. If the sensor check is completed, the ABS warning light blinks (Test Mode) when the vehicle stops and the ABS warning light is off while the vehicle is driving.
      NOTE:
      • When the yaw rate sensor, acceleration sensor, speed sensor and master cylinder pressure sensor checks are completed, the sensor check is completed.
      • If the sensor check is not completed, the ABS warning light blinks even while the vehicle is driving and the ABS does not operate.
        Fig 8: ABS Warning Light Blinking Pattern In Test Mode
        G05319286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. READ DTC OF SIGNAL CHECK FUNCTION (WHEN USING INTELLIGENT TESTER:) 
    1. Read the DTC (s) by following the tester screen.
      NOTE:
      • If only the DTCs are displayed, repair the malfunction area and clear the DTCs.
      • If the DTCs or Test Mode codes (DTC of signal check function) are displayed, repair the malfunction area, clear the DTCs and perform the Test Mode inspection.

      HINT:

      See the list of DTCs (see DIAGNOSTIC TROUBLE CODE CHART  ).

  10. SENSOR SIGNAL CHECK BY TEST MODE (SIGNAL CHECK) (WHEN USING SST CHECK WIRE:) 
    NOTE: After replacement of the skid control ECU and/or yaw rate and acceleration sensor, perform zero point calibration of the yaw rate and acceleration sensor.

    HINT:

    • If the engine switch is turned from on (IG) to on (ACC) or off during Test Mode (signal check), DTCs of the signal check function will be erased.
    • During Test Mode (signal check), the skid control ECU records all DTCs of the signal check function. By performing the Test Mode (signal check), the codes are erased if a normal condition is confirmed. The remaining codes are the codes where an abnormality was found.
    1. Procedure for Test Mode.
      1. Turn the engine switch off.
      2. Check that the steering wheel is centered and move the shift lever to the P position.
      3. Using SST, connect terminals TS and CG of the DLC3.

        SST 09843-18040 

      4. Turn the engine switch on (IG).
        Fig 9: Identifying Terminals TS And CG Of DLC3 Connector
        G05319287Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Check that the ABS warning light, and master caution indicator light blink and "VSC TEST MODE" is displayed on the multi-information display (Test Mode).

        HINT:

        If the ABS and VSC warning (multi-information display and master caution indicator light) lights do not blink, inspect the TS and CG terminal circuit, and ABS and VSC warning light circuit.

        TROUBLESHOOTING CHART

        Trouble Area See procedure
        TS and CG terminal circuit TS AND CG TERMINAL CIRCUIT 
        ABS warning light circuit ABS WARNING LIGHT DOES NOT COME ON 
        VSC warning light circuit VSC WARNING LIGHT DOES NOT COME ON 
        Fig 10: Identifying Indicator Light Blinking Pattern And VSC TEST MODE Display
        G05319288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Check the ABS sensor.

        HINT:

        Check that the ABS warning light is blinking in Test Mode and perform the check.

  11. LOST BOOSTER PRESSURE JUDGEMENT CHECK AND MASTER CYLINDER PRESSURE SENSOR ZERO POINT CALIBRATION (WHEN USING SST CHECK WIRE:) 
    NOTE: Perform the check in the lost booster pressure state (negative pressure in the booster is depressurized).
    Fig 11: ABS Warning Light Blinking Pattern In Test Mode
    G05319289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the engine switch on (IG).
    2. Check that the BRAKE warning light comes on when depressing the brake pedal with a force of 59 N (6 kgf, 13.2 lbf) or more for 1 second or more. (The lost booster pressure state is judged normal.)
    3. Start the engine depressing the brake pedal with a force of 59 N (6 kgf, 13.2 lbf) or more for 1 second or more.
    4. Check that the BRAKE warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged normal.)
    5. Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)
      NOTE:
      • If you slowly depress the brake pedal or depress it again, master cylinder pressure sensor zero point calibration is not performed normally.
      • If lost booster pressure judgment check is not completed normally, master cylinder pressure sensor check is not judged.
      • If recheck is performed after the engine has started, end the Test Mode, transit to the Test Mode again, and release the vacuum in the booster by pumping the brake pedal prior to the recheck.
  12. ACCELERATION SENSOR CHECK (WHEN USING SST CHECK WIRE:) 
    1. Keep the vehicle stationary on a level surface for 1 second or more.

      HINT:

      The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

  13. MASTER CYLINDER PRESSURE SENSOR CHECK (WHEN USING SST CHECK WIRE:) 
    1. Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, and quickly and continuously depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second.
    2. Check that the ABS warning light stays on for 3 seconds.

      HINT:

      • Ensure that the ABS warning light comes on.
      • While the ABS warning light stays on, continue to depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more.
      • The ABS warning light comes on for 3 seconds every time the brake pedal operation above is performed.
      • If the check of the master cylinder pressure sensor is not completed, depressing the brake pedal causes further decrease in the negative pressure, making the sensor check difficult to be completed.
      • If the negative pressure is insufficient, the master cylinder pressure sensor check may not be completed. In this case, run the engine at idle to obtain sufficient negative pressure.
      • If the brake pedal is strongly depressed when the negative pressure is insufficient, the BRAKE warning light may come on in accordance with the booster pressure control. In this case, run the engine at idle to obtain sufficient negative pressure.
  14. SPEED SENSOR CHECK (WHEN USING SST CHECK WIRE:) 
    1. Check the reverse signal.
      1. Drive the vehicle in reverse for more than 1 second at 2 mph (3 km/h) or more.

        HINT:

        Drive the vehicle in reverse and check the speed sensor signal. The sensor check cannot be completed if the vehicle speed is 28 mph (45 km/h) or more.

    2. Check the forward signal.
      1. Drive the vehicle straight ahead.

        Accelerate the vehicle to a speed of 28 mph (45 km/h) or more for several seconds and check that the ABS warning light goes off.

        HINT:

        The sensor check may not be completed if the vehicle has its wheels spun.

    3. Stop the vehicle.
      NOTE:
      • Before performing the speed sensor check, complete the acceleration sensor and master cylinder pressure sensor checks.
      • The speed sensor check may not be completed if the speed sensor check is started while turning the steering wheel or spinning the wheels.
      • After the ABS warning light goes off, if vehicle speed exceeds 50 mph (80 km/h), a signal check code will be stored again. Accelerate or stop the vehicle before the speed reaches 50 mph (80 km/h).
      • If the signal check has not been completed, the ABS warning light blinks while driving and the ABS system does not operate.
      • If the vehicle is driven in reverse at 28 mph (45 km/h) or more, the sensor check will not be completed.

      HINT:

      When the sensor check has been completed, the ABS warning light goes off while driving and blinks in the Test Mode pattern while stationary.

    4. Check the VSC sensor.

      Check that the master caution indicator light blinks and "VSC TEST MODE" is displayed on the multi-information display, and perform the check.

      Fig 12: Identifying Indicator Light Blinking Pattern And VSC TEST MODE Display
      G05319290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  15. YAW RATE SENSOR CHECK (WHEN USING SST CHECK WIRE:) 
    1. Check the output of the yaw rate sensor.
      1. Keep the vehicle stationary on a level surface for 1 second or more.
      2. Move the shift lever from the P to the D position and drive the vehicle at a vehicle speed of approximately 3 mph (5 km/h) and turn the steering wheel either to the left or right 90° or more and until the vehicle makes a 180° turn.
        Fig 13: Identifying Vehicle Start And Stop Position
        G05319291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Stop the vehicle and move the shift lever to the P position. Check that the skid control buzzer sounds for 3 seconds.

        HINT:

        • If the skid control buzzer sounds, the sensor check is completed normally.
        • If the skid control buzzer does not sound, check the skid control buzzer circuit (See SKID CONTROL BUZZER CIRCUIT  ), then perform the sensor check again.
        • If the skid control buzzer still does not sound, there is a malfunction in the yaw rate sensor, so check the DTC.
        • At the end of the 180° turn, the direction of the vehicle should be within 175° to 185° of its start position.
        • Do not spin the wheels.
        • Do not turn the engine switch off while turning.
        • Do not move the shift lever to the P position while turning, but changing in the vehicle speed, stopping, or driving in reverse is possible.
        • Complete the turn within 20 seconds.
  16. END OF SENSOR CHECK (WHEN USING SST CHECK WIRE:) 
    1. If the sensor check is completed, the ABS warning light blinks (Test Mode) when the vehicle stops and the ABS warning light is off while the vehicle is driving.
      NOTE:
      • When the yaw rate sensor, acceleration sensor, speed sensor and master cylinder pressure sensor checks are completed, the sensor check is completed.
      • If the sensor check is not completed, the ABS warning light blinks even while the vehicle is driving and the ABS does not operate.
        Fig 14: ABS Warning Light Blinking Pattern In Test Mode
        G05319292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  17. READ DTC OF SIGNAL CHECK FUNCTION (WHEN USING SST CHECK WIRE:) 
    1. Using SST, connect terminals TS and CG, TC and CG of the DLC3.

      SST 09843-18040 

      Fig 15: Identifying DLC3 Connector Terminals
      G05319293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Count the number of blinks of the ABS warning light and read the "DIAG VSC" on the multi-information display.
      Fig 16: ABS Warning Light Blinking Pattern And DIAG VSC Display
      G05319294Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • If only the DTCs are displayed, repair the malfunction area and clear the DTCs.
      • If the DTCs or Test Mode codes (DTC of signal check function) are displayed, repair the malfunction area, clear the DTCs and perform the Test Mode inspection.

      HINT:

      • If more than 1 malfunction is detected at the same time, the lowest numbered code will be displayed first.
      • See the list of DTC (see DIAGNOSTIC TROUBLE CODE CHART  ).
    3. After performing the check, disconnect SST from terminals TS and CG, and TC and CG of the DLC3. Then turn the engine switch off.
    4. Turn the engine switch on (IG).

      HINT:

      • If the engine switch is not turned on (IG) after SST is removed from the DLC3, the previous Test Mode will continue.
      • If the engine switch is turned on (IG) with terminals TS and CG shorted, the previous Test Mode will continue.
  18. DTC OF TEST MODE (SIGNAL CHECK) FUNCTION 

    ABS sensor: 

    ABS SENSOR DTC CHART

    Code No. Diagnosis Trouble Area
    C1270/88 Initialization incomplete
    • ECM
    • CAN communication system (Skid control ECU to ECM)
    • Skid control ECU
    C1271/71 Low output signal of front speed sensor RH
    • Front speed sensor RH
    • Sensor installation
    • Speed sensor rotor
    C1272/72 Low output signal of front speed sensor LH
    • Front speed sensor LH
    • Sensor installation
    • Speed sensor rotor
    C1273/73 Low output signal of rear speed sensor RH
    • Rear speed sensor RH
    • Sensor installation
    • Speed sensor rotor
    C1274/74 Low output signal of rear speed sensor LH
    • Rear speed sensor LH
    • Sensor installation
    • Speed sensor rotor
    C1275/75 Abnormal change in output signal of front speed sensor RH Speed sensor rotor
    C1276/76 Abnormal change in output signal of front speed sensor LH Speed sensor rotor
    C1277/77 Abnormal change in output signal of rear speed sensor RH Speed sensor rotor
    C1278/78 Abnormal change in output signal of rear speed sensor LH Speed sensor rotor
    C1279/79 Acceleration sensor output voltage malfunction
    • Yaw rate and acceleration sensor
    • Sensor installation
    C1281/81 Master cylinder pressure sensor output malfunction
    • Stop light switch
    • Brake pedal load sensing switch
    • Master cylinder pressure sensor

    VSC sensor: 

    VSC SENSOR DTC CHART

    Code No. Diagnosis Trouble Area
    C0371/71 Yaw rate sensor Yaw rate and acceleration sensor

    HINT:

    The codes in this table are output only in Test Mode (signal check).