Steering Lock System (Diagnostics - Introduction): Diagnosis Lexus GX J150

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

1. Use the following procedures to troubleshoot the steering lock system.
2. *: Use the Techstream.

1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
2. CUSTOMER PROBLEM ANALYSIS NEXT: Go to next step
3. INSPECT BATTERY VOLTAGE Standard voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding. HINT: A simple method to determine whether the battery is depleted is to operate the horn. NEXT: Go to next step
4. CHECK DTC* Check for DTCs and make a note of any codes that are output. Refer to «DTC CHECK / CLEAR»(ref-524329-S02639288412013012800000) . RESULT Result Proceed to No DTCs output Problem symptom can be confirmed and reproduced A Problem symptom cannot be confirmed or reproduced B Steering lock system DTCs output C LIN communication DTCs output D HINT: When steering lock system DTCs are output, refer to Diagnostic Trouble Code Chart. Refer to «DIAGNOSTIC TROUBLE CODE CHART»(ref-524329-S22425066912013012800000) . The steering lock system does not store past DTCs. B --> USE SIMULATION METHOD TO CHECK. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-524109-S12033069852013012800000) C --> Go to step 7 D --> Go to LIN COMMUNICATION SYSTEM (DIAGNOSTIC TROUBLE CODE CHART). Refer to «DIAGNOSTIC TROUBLE CODE CHART»(ref-524330-S17432023512013012800000) A: Go to next step
5. PROBLEM SYMPTOMS TABLE Refer to Problem Symptoms Table. Refer to «PROBLEM SYMPTOMS TABLE»(ref-524329-S31726256182013012800000) . RESULT Result Proceed to Fault not listed in problem symptoms table A Fault listed in problem symptoms table B B --> Go to step 6 A: Go to next step
6. OVERALL ANALYSIS AND TROUBLESHOOTING* Data List / Active Test. Refer to «DATA LIST / ACTIVE TEST»(ref-524329-S33185131592013012800000) . Terminals of ECU. Refer to «TERMINALS OF ECU»(ref-524329-S12025935462013012800000) . NEXT: Go to next step
7. REPAIR OR REPLACE NEXT: Go to next step
8. CHECK DTC AGAIN* Clear the DTCs. Refer to «DTC CHECK / CLEAR»(ref-524329-S02639288412013012800000) . Check for DTCs and make a note of any codes that are output. Refer to «DTC CHECK / CLEAR»(ref-524329-S02639288412013012800000) . HINT: Perform the DTC output confirmation operation. RESULT Result Proceed to No DTCs output A DTCs output B B --> GO TO DIAGNOSTIC TROUBLE CODE CHART A --> END

PROBLEM SYMPTOMS TABLE

HINT

1. Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
2. Inspect the fuses and relays related to this system before inspecting the suspected areas below.

STEERING LOCK SYSTEM

Scheme 60

Scheme 61

1. CHECK STEERING LOCK ECU Measure the voltage and resistance according to the value(s) in the table below. Terminal No. (Symbol) Input/Output Wiring Color Terminal Description Condition Specified Condition Related Data List Item G23-1 (GND) - Body ground - W-B - Body ground Ground* Always Below 1 ohms - G23-3 (IGE) - G23-1 (GND) Input W - W-B Steering lock motor activation command signal (motor activation command signal sent from power management control ECU) Any door opened when conditions below met, and then steering lock motor activated: Shift lever in P Steering lock unlocked in advance by carrying key and turning engine switch on (IG) After above condition met, engine switch turned off Pulse generation (See Waveform) Smart Access Power Supply Short Power Supply Open Unlock Request Receive Lock Request Receive G23-4 (SLP1) - G23-1 (GND) Output SB - W-B Steering lock bar position signal (output signal from steering unlock sensor) Steering locked --> unlocked 11 to 14 V --> Below 1.2 V Smart Access Push Start Error Sensor Value G23-5 (LIN) - G23-1 (GND) Input/Output G - W-B LIN communication line - - Smart Access Steering Lock Start Cond IG(Lin) G23-6 (IG2) - G23-1 (GND) Input W - W-B Power source mode signal (IG2 power supply input for entire steering lock actuator)* Engine switch off --> engine switch on (IG) Below 1 V --> 11 to 14 V Smart Access Ignition Switch IG2 Status IG(Lin) G23-7 (B) - Body ground Input G - Body ground Power source* Always 11 to 14 V - *: When there is a problem with the power source input, the certification ECU may store DTC B2786. NOTE: There is 1 motor and 2 sensors built into the steering lock actuator. HINT: When taking measurements when the lock motor is stopped, it is not necessary to perform any operations. In order to take measurements when the lock motor is operating, perform either of the following operations: To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG) while the shift lever is in P. To lock the steering, turn the engine switch off with the shift lever in P, and then open a door. Waveform Item Content Tester Connection G23-3 (IGE) - G23-1 (GND) Tool Setting 2 V/DIV., 200 ms./DIV. Vehicle Condition Steering lock motor not operating --> Steering lock motor operating --> Steering lock motor not operating TEXT IN ILLUSTRATION *a Steering lock motor not operating *b Steering lock motor operating

DIAGNOSIS SYSTEM

1. DESCRIPTION The steering lock ECU stores DTCs when a malfunction occurs in the system. These DTCs can be confirmed by using the Techstream. NOTE: When using the Techstream with the engine switch off to confirm DTCs or Data List information related to the smart access system with push-button start, the Techstream may not operate unless either of the following is performed: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Access / Trouble Codes. Do not remove any fuses or disconnect the cable from the negative (-) battery terminal before confirming and recording DTCs as the data stored in the ECUs will be cleared. DTCs may have been stored due to problems unrelated to the steering lock ECU system. Be sure to confirm and record any DTCs output for other systems. The steering lock ECU is not connected to the CAN communication system. Therefore, communication with the Techstream is performed via the certification ECU. The steering lock ECU only stores DTCs for currently existing malfunctions. Past DTCs are not stored.

DTC CHECK / CLEAR

Note. The steering lock ECU does not store past DTCs. If any DTCs are output, confirm and record them as soon as possible. Do not turn the engine switch off or clear the DTCs until the DTCs are confirmed and recorded. DTCs may have been stored due to problems unrelated to the steering lock ECU system. Be sure to confirm and record any DTCs output for other systems. When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Access / Trouble Codes.

1. CHECK FOR DTC (MAIN BODY ECU) Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Main Body / Trouble Codes. Check for DTCs.
2. CHECK FOR DTC (CERTIFICATION ECU) HINT: The steering lock system DTCs are output from the steering lock ECU via the certification ECU. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Smart Access / Trouble Codes. Check for DTCs.
3. CLEAR DTC (MAIN BODY ECU) Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Main Body / Trouble Codes. Clear the DTCs.
4. CLEAR DTC (CERTIFICATION ECU) Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Smart Access / Trouble Codes. Clear the DTCs.

Scheme 62

1. READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time. NOTE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not. Turn the engine switch off. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / (desired system) / Data List. According to the display on the Techstream, read the Data List. Using the Techstream, confirm the Data List items to help determine the cause of the problem. NOTE: The steering lock ECU communicates with the Techstream through the certification ECU which uses CAN communication. If the CAN communication system or certification ECU is malfunctioning, Data List items may not be normal. When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Access / Data List. POWER SOURCE CONTROL Tester Display Measurement Item/Range Normal Condition Diagnostic Note Shift P Signal Shift position (P)/ON or OFF ON: Shift lever in P OFF: Shift lever not in P Use this item to determine if the shift position switch is malfunctioning. The engine cannot be started when this item is "OFF". Steering Unlock Switch State of steering unlock sensor signal output from steering lock actuator assembly/ON or OFF ON: Steering unlocked (Engine switch on [ACC]) OFF: Steering locked (Engine switch off door opened) This item can be used to determine the cause of problems when the steering does not lock or unlock. HINT: The steering is considered locked when the lock sensor is ON and the unlock sensor is OFF. The steering is considered unlocked when the lock sensor is OFF and the unlock sensor is ON. Str Lock/Unlock Wait T-Out Steering lock or unlock malfunction/ Yes or No Yes: Steering lock/unlock timed out (Lock bar stuck, etc.) No: Steering locks/unlocks normally within specified time The engine cannot be started when this item is "Yes". SMART ACCESS Tester Display Measurement Item/Range Normal Condition Diagnostic Note Ignition Switch State of certification ECU IG power supply input/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off This item displays "OFF" when the engine switch is on (ACC). #Codes Number of DTCs/0 to 255 - - Immobiliser State of immobiliser system determined by certification ECU/Set or Unset Set: Engine immobiliser set (engine switch off) Unset: Engine immobiliser unset (engine switch on [ACC] or on [IG]) When the immobiliser cannot be unset, this item can be used to determine whether the certification ECU or ID code box is part of the problem. The engine cannot be started when this item displays "Set". HINT: The state of the immobiliser (whether it is set or unset) can be determined through the certification ECU. If this item displays "Set", the communication between the certification ECU and ID code box can be determined to be normal. The security indicator light operation is only linked with the state of the immobiliser (set/unset), and is not related to the steering lock operation (lock/unlock), when the immobiliser is set, the security indicator light blinks. Steering Lock Sleep Cond Steering lock ECU sleep condition/Yes or No - - Steering Lock Start Cond Transmission state of steering lock ECU wake up signal/Yes or No Yes: Wake up signal transmitted No: Wake up signal not transmitted - Engine Start Condition State of engine start permission signal determined by steering lock actuator assembly (steering lock ECU) and sent to certification ECU/OK or NG OK: Engine start permitted NG: Engine start prohibited When this item displays "OK", the certification ECU has received an unlock confirmation signal from the steering lock ECU and has permitted fuel injection and engine combustion. The engine cannot be started when this item displays "NG". Sensor Value Malfunction history of position sensor in steering lock actuator/OK or NG(Past) OK: No record of lock/unlock sensor malfunction in steering lock actuator NG(Past): Record of lock/unlock sensor in steering lock actuator turning ON at same time exists When this item displays "NG", the sensor inside the steering lock actuator may be malfunctioning, or there may be a mechanical malfunction. Power Supply Short Record of malfunction of signal sent to steering lock actuator assembly (motor) from power management control ECU (short circuit)/OK or NG(Past) OK: No record of malfunction (short circuit) NG(Past): Record of malfunction (short circuit) exists This item records malfunctions in the circuit between the power management control ECU and steering lock actuator assembly (motor). Power Supply Open Record of malfunction of signal sent to steering lock actuator assembly (motor) from power management control ECU (open circuit) (DTC B2782 stored)/OK or NG(Past) OK: No record of malfunction (open circuit) NG(Past): Record of malfunction (open circuit) exists This item records malfunctions in the circuit between the power management control ECU and steering lock actuator assembly (motor). Motor Driver Short Record of malfunction of motor activation circuit in steering lock actuator assembly (short circuit) (DTC B2781 stored)/OK or NG(Past) OK: No record of malfunction (short circuit) NG(Past): Record of malfunction (short circuit) exists This item records malfunctions in the motor activation circuit inside the steering lock actuator assembly (short circuit). Motor Driver Open Record of malfunction of motor activation circuit in steering lock actuator assembly (open circuit) (DTC B2781 stored)/OK or NG(Past) OK: No record of malfunction (open circuit) NG(Past): Record of malfunction (open circuit) exists This item records malfunctions in the motor activation circuit inside the steering lock actuator assembly (open circuit). Lock/Unlock Receive Reception state of steering lock or unlock request signal from certification ECU/Yes or No Yes: Record of receiving lock or unlock request signal exists No: No record of receiving lock or unlock request signal - Lock Bar Stuck Error Record of lock bar not properly unlocking after being commanded to unlock for certain amount of time/OK or NG(Past) OK: No record of stuck lock bar NG(Past): Record of stuck lock bar exists - Push Start Error Record of malfunction of push-start function due to steering lock actuator/OK or NG(Past) OK: No record of push-start function malfunction NG(Past): Record push-start function malfunction exists - IG2 Status State of steering lock actuator assembly IG power supply input (direct line)/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off As this is the IG2 relay ON signal, this item displays "OFF" when the engine switch is on (ACC). IG(Lin) State of IG signal from LIN communication recognized by steering lock actuator assembly/ON or OFF ON: Engine switch on (IG) OFF: Engine switch off The display is the same as "IG2 Status". Engine Start Request Reception state of engine start permission signal determined by steering lock actuator assembly and sent to certification ECU/OK or NG OK: Receiving signal NG: Not receiving signal When this item displays "OK", the certification ECU has received an unlock confirmation signal from the steering lock ECU and has permitted fuel injection and engine combustion. The engine cannot be started when this item displays "NG". S Code Check Verification result between certification ECU and ID code box/OK or NG OK: Verification result normal NG: Verification result abnormal When a malfunction is present: The ID code for the certification ECU or ID code box is not registered or the certification ECU or ID code box is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started). L Code Check Verification result between ID code box and steering lock actuator assembly/OK or NG OK: Verification result normal NG: Verification result abnormal When a malfunction is present: The ID code for the ID code box or steering lock actuator assembly is not registered or the ID code box or steering lock actuator is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started). Unlock Request Receive Reception state of steering unlock command signal sent to ID code box determined by certification ECU/OK or NG HINT: The reception state is maintained for 10 seconds. When 10 seconds or more elapse after receiving the signal, the item changes to "NG". OK: Within 10 seconds of turning engine switch on (IG) or on (ACC) or starting engine NG: Except above If the unlock signal has not been received, the engine cannot be started. If this item does not change to "OK" even though the steering unlock conditions are met, the certification ECU may be malfunctioning. Lock Request Receive Reception state of steering lock command signal sent to ID code box determined by certification ECU/OK or NG HINT: The reception state is maintained for 10 seconds. When 10 seconds or more elapse after receiving the signal, the item changes to "NG". OK: Within 10 seconds of opening any door with engine switch off and shift lever in P NG: Except above If this item does not change to "OK" even though the steering lock conditions are met, the certification ECU may be malfunctioning. S Code Check(Past) Verification result between certification ECU and ID code box (Past)/OK or NG(Past) OK: Verification result normal NG(Past): Verification result abnormal (Past) - L Code Check(Past) Verification result between ID code box and steering lock actuator assembly (Past)/OK or NG(Past) OK: Verification result normal NG(Past): Verification result abnormal (Past) - Steering Lock State of whether steering lock ECU has determined steering is locked/Set or Unset Set: Steering locked Unset: Steering unlocked If this item displays "Unset", the steering does not lock. Steering Unlock State of whether steering lock ECU determined steering is unlocked/Set or Unset Set: Steering unlocked Unset: Steering locked If this item displays "Unset", the steering does not unlock (engine cannot be started). HINT: Unlock operation conditions for the steering lock: When the following condition is met, the unlock operation is performed: The engine switch is on (ACC) or on (IG). When the engine switch is turned on (ACC) or on (IG) and the key and certification ECU are verified, the steering is unlocked. When any of the following conditions are met, key verification is performed. The brake pedal is depressed so that the engine can be started. 30 seconds elapse after opening and closing a door. The engine switch is pressed. Key verification occurs when the code emitted from the key and the code stored in the certification ECU are compared to check that they match. Certification ECU verification occurs when the S code and L code are verified while the engine is being started or the engine switch is being pushed. The ID code box uses the S code to determine whether the certification ECU is authorized. The steering lock ECU uses the L code to determine whether the ID code box is authorized. Lock operation conditions for the steering: When the following conditions are met and the certification ECU has been verified, the lock operation is performed. The engine switch is off. The shift lever is in P. A door is opened or a door lock operation (smart door lock, wireless door lock or key-linked lock) is performed. HINT: The following example shows the behavior of various Data List items when the shift lever is in P, the brake pedal is not depressed, the vehicle is normal and the power source mode changes. HINT: Get into the vehicle while carrying the key. With the engine switch off, the shift lever in P and all the doors closed, perform the following procedures and check the power source mode. *1: Without depressing the brake pedal, press the engine switch and check that the power source mode turns on (ACC). *2: Without depressing the brake pedal, press the engine switch and check that the power source mode turns on (IG). *3: Press the engine switch and check that the power source mode turns off. *4: Release the brake pedal, open the driver side door and check that the steering locks. MAIN BODY Tester Display Measurement Item/Range Normal Condition Diagnostic Note FL Door Courtesy Front door courtesy switch LH/ON or OFF ON: Front door LH closed OFF: Front door LH open If this item does not change according to the actual state of the driver side door, there is a malfunction in the door courtesy light switch or related part.

DIAGNOSTIC TROUBLE CODE CHART

HINT

If a trouble code is output during the DTC check, refer to the "See page" below.

STEERING LOCK SYSTEM