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Home >> Lexus >> 2012 >> IS F >> Repair and Diagnosis (Single Page) >> Steering >> Steering Column >> Steering Lock System (Diagnostics - Introduction) >> Steering Lock System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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STEERING LOCK FUNCTION

Symptom Suspected Area Refer To
Steering wheel cannot be unlocked (the engine cannot be started). Initialization Refer to INITIALIZATION 
Check for DTCs in the smart access system with push-button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
Check for DTCs in the engine immobiliser system. Refer to DIAGNOSTIC TROUBLE CODE CHART
Check that the LCK/UNLOCK REC item in the Data List of the certification ECU displays YES within 10 seconds after starting the engine. (I it displays NO, see "No steering unlock command" in this table.) Refer to DATA LIST / ACTIVE TEST 
Check the output from the IGE terminal of the steering lock ECU. Refer to Steering Lock Motor Drive Power Circuit
Steering lock ECU power source circuit. Refer to Power Source Circuit
Replace the steering lock ECU. Refer to DISASSEMBLY
Steering wheel cannot be unlocked (no steering unlock command). Check that the S CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Check that the L CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Replace the certification ECU. -
Steering wheel cannot be locked. Check for DTCs in the smart access system push-button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
Check for DTCs in the engine immobiliser system. Refer to DIAGNOSTIC TROUBLE CODE CHART
With the engine switch off and the shift lever in P, open and close the driver door. After that, check that the LCK/UNLOCK REC item in the Data List of the certification ECU displays YES within 10 seconds. (If it displays NO, see "No steering lock command" in this table.) Refer to DATA LIST / ACTIVE TEST 
Check the output from the IGE terminal of the steering lock ECU. Refer to Steering Lock Motor Drive Power Circuit
Steering lock ECU power source circuit. Refer to Power Source Circuit
Replace the certification ECU. -
Steering wheel cannot be locked (no steering lock command). Courtesy light switch circuit Refer to Door Courtesy Switch Circuit
Check that the S CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Check that the L CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Replace the certification ECU. -
PUSH BUTTON START FUNCTION

Symptom Suspected Area Refer To
Engine does not start. Initialization Refer to INITIALIZATION 
Check for DTCs in the smart access system with push-button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
Check for DTCs in the engine immobiliser system. Refer to DIAGNOSTIC TROUBLE CODE CHART
Check that the engine switch is turned on. -
Check cranking operation. (If cranking operation is possible, see "Engine dose not start due to the engine immobiliser" in this table.) -
Check the SHIFT P SIG item in the Data List of the power source control ECU and confirm that the shift signal is normal. -
Check whether the steering wheel is locked or unlocked. (If it is locked, see "Steering wheel cannot be unlocked" in the steering lock function table.) -
Check the output from the SLP1 terminal of the steering lock ECU. Refer to Unlock Position Sensor Signal Circuit
Check the output signal from the engine switch of the certification ECU (DTC B2275). Refer to DTC B2275: STSW Monitor Malfunction
Replace the power source control ECU. -
Engine does not start due to the engine immobiliser. Check that the L CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Check that the ENG START REQ item in the Data List of the certification ECU displays YES. (If it displays NO, replace the certification ECU.) Refer to DATA LIST / ACTIVE TEST 
Check that the S CODE MACH item in the Data List of the certification ECU displays OK. (If it displays NG, replace the ID code box.) Refer to DATA LIST / ACTIVE TEST 
Replace the ID code box. -