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Home >> Mitsubishi >> 2005 >> Lancer Evolution RS >> Repair and Diagnosis (Single Page) >> Brakes >> Traction Control >> Abs (Anti-Lock Brake System) - Evolution >> Anti-Lock Braking System (Abs) Diagnosis >> Symptom Procedures >> INSPECTION PROCEDURE 6: The Neutral Position Learning of the Steering Angular Velocity Sensor is not Detected. >> Diagnosis
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INSPECTION PROCEDURE 6: The Neutral Position Learning of the Steering Angular Velocity Sensor is not Detected.: Diagnosis

Required Special Tools: 

  1. STEP 1. Check the front tires. 

    Q: Are the tire diameters different? 

    • YES :  Replace the appropriate tire and then go to  Step 13.
    • NO :  Go to Step 2.
  2. STEP 2. Check the front suspension. 

    Q: Is the front suspension abnormal? 

    • YES :  Repair the front suspension and then go to  Step 13.
    • NO :  Go to Step 3.
  3. STEP 3. Using scan tool MB991958, check data list. 
    CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOOK" (OFF) position before connecting or disconnecting scan tool MB991958.
    1. Connect scan tool MB991958 as shown in the illustration.
    2. Start the engine.
    3. Set scan tool MB991958 to data reading mode for following item.
      • Item 37: Steering angular sensor neutral position learning
    4. Confirm the indicated ON/OFF state as follows:
      DATA LIST DISPLAY

      CHECKING REQUIREMENT DISPLAY
      After driving straight at vehicle speed over than 10 km/h (6.3 mph) ON
      Before driving with ignition switch ON OFF

    Q: Is the steering angular velocity sensor straight ahead position learning input normal? 

    • YES :  Go to  Step 5.
    • NO :  Confirm the steering angular velocity sensor is correctly installed. Then go to Step 4.
    Fig 1: Connecting Scan Tool To Data Link Connector
    G02403433Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  4. STEP 4. Check for steering angular velocity sensor output voltage. 
    1. Connect steering angular velocity sensor connector C-230.
    2. Turn the ignition switch to the "ON" position.
      Fig 2: Checking Steering Angular Velocity Sensor Output Voltage
      G02403434Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Measure the voltage, by backprobing, between terminal 1 and ground, terminal 4 and ground, and terminal 5 and ground. The voltage should measure as indicated in the figure.

    Q: Is the steering angular velocity sensor output voltage normal? 

    Fig 3: Steering Angular Velocity Sensor Output Voltage Graph
    G02403435Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  5. STEP 5. Check the stoplight. 

    Q: Does the stoplight turn on and off normally? 

    • YES :  Go to  Step 9.
    • NO :  Go to Step 6.
  6. STEP 6. Check the stoplight switch installation condition. 

    Q: Is the stoplight switch installed correctly? 

  7. STEP 7. Check the following connectors. 
    • Intermediate connectors C-129
    • Stoplight switch connector C-102

    Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.

    Q: Are the connectors and terminals in good condition? 

    • YES :  Go to Step 8.
    • NO :  Repair it and then go to  Step 13.
    Fig 4: Identifying Intermediate Connectors C-129 And Stoplight Switch Connector C-102
    G02403436Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  8. STEP 8. Check the following harness wires. 
    • The wire between relay box in engine compartment (fuse No. 10) and stoplight switch connector C-102 (terminal 2)
    • The wire between stoplight switch connector C-102 (terminal 1) and stoplights

    Q: Is any harness wire damaged? 

    • YES :  Repair or replace it and then go to  Step 13.
    • NO :  Go to Step 9.
    Fig 5: Locating Fuse No. 10
    G02403437Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 6: Identifying Stoplight Switch Connector C-102
    G02403438Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  9. STEP 9. Check the stoplight switch circuit. Measure the voltage at ABS-ECU connector B-118. 
    1. Disconnect ABS-ECU connector B-118 and measure at the harness side.
    2. Depress the brake pedal to turn on the stoplight switch.
    3. Measure the voltage between terminal 19 and ground. It should measure battery voltage (approximately 12 volts).

    Q: Is battery positive voltage (approximately 12 volts) present? 

    • YES :  Go to  Step 12.
    • NO :  Go to Step 10.
    Fig 7: Measuring Voltage Between Terminal 19 And Ground
    G02403439Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  10. STEP 10. Check the following connectors. 
    • ABS-ECU connector B-118
      Fig 8: Identifying ABS-ECU Connector B-118
      G02403440Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    • Joint connector C-105
    • Intermediate connector C-124
    • Stoplight switch connector C-102

    Check the connectors for loose, corroded or damaged terminals, or terminals pushed back in the connector.

    Q: Are the connectors and terminals in good condition? 

    • YES :  Go to Step 11.
    • NO :  Repair it and then go to  Step 13.
    Fig 9: Identifying Joint Connector C-105 And Intermediate Connector C-124
    G02403441Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  11. STEP 11. Check the following harness wire. 

    The wire between stoplight switch connector C-102 (terminal 1) and ABS-ECU connector B-118 (terminal 19)

    Q: Is the harness wire damaged? 

    • YES :  Repair or replace it and then go to  Step 13.
    • NO :  Go to  Step 13.
    Fig 10: Identifying Stoplight Switch Connector C-102
    G02403442Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 11: Identifying ABS-ECU Connector B-118
    G02403443Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  12. STEP 12. Check the following connector. 

    ABS-ECU connector B-118

    Check the connector for loose, corroded or damaged terminals, or terminals pushed back in the connector.

    Q: Are the connector and terminals in good condition? 

    • YES :  Replace the brake modulator hydraulic unit (integrated with ABS-ECU) (Refer to HYDRAULIC UNIT ). Then go to Step 13.
    • NO :  Repair it and then go to Step 13.
    Fig 12: Identifying ABS-ECU Connector B-118
    G02403444Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  13. STEP 13. Retest the system. 

    Q: Is the neutral position learning of the steering angular velocity sensor detected by the ABS system? 

    • YES :  The procedure is complete.
    • NO :  Return to Step 1.