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Home >> Lexus >> 2013 >> IS F >> Repair and Diagnosis >> Brakes >> Traction Control >> Vehicle Stability Control System (Diagnostic Codes & Symptom Tests) >> Vehicle Stability Control System >> DTC C1203: ECM Communication Circuit Malfunction; DTC C1270: Initialization Incomplete (Test Mode DTC) >> Procedure
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DTC C1203: ECM Communication Circuit Malfunction; DTC C1270: Initialization Incomplete (Test Mode DTC): Procedure

  1. CHECK PART NUMBER (ECM) 
    1. Check that the part number of the installed ECM is correct.

      OK

      ECM installed in the vehicle has the correct part number.

    NG → See step   6 

    OK: Go to next step 

  2. CLEAR AND STORE SYSTEM INFORMATION 
    1. Clear the system information. Refer to CALIBRATION [08/2012 - ] .
    2. Store the system information. Refer to CALIBRATION [08/2012 - ] .

    NEXT: Go to next step 

  3. RECONFIRM DTC 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2012 - ] .
    2. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR [08/2012 - ] .

      Result

      Result Proceed to
      DTC (C1203) is not output A
      DTC (C1203) is output B

    B → See step   5 

    A → See step   4 

  4. CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ] 
  5. REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [08/2012 - ] 
  6. REPLACE ECM (for 2UR-GSE). Refer to  REMOVAL [08/2012 - ]