Steering Lock System (Diagnostics - Introduction): Diagnosis Lexus IS III

PROBLEM SYMPTOMS TABLE [04/2013 - ]

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 65

Scheme 66

1. TERMINAL INSPECTION *a Component without harness connected (Steering Lock ECU (Steering Lock Actuator Assembly)) 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 K28-1 (GND) - Body ground - W-B - Body ground Ground* Always Below 1 ohms - K28-3 (IGE) - K28-1 (GND) Input W - W-B Steering lock motor activation command signal (motor activation command signal sent from certification ECU (smart key ECU assembly)) 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 conditions met, engine switch turned off Pulse generation (see waveform) Smart Access Power Supply Short Unlock Request Receive Lock Request Receive K28-4 (SLP1) - K28-1 (GND) Output R - W-B Steering lock bar position signal (output signal from steering unlock sensor) Steering locked --> unlocked 11 to 14 V --> Below 1.5 V Smart Access Sensor Value K28-5 (LIN) - K28-1 (GND) Input/Output V - W-B LIN communication line - - Smart Access Steering Lock Start Cond K28-6 (IG2) - K28-1 (GND) Input B - W-B Power source mode signal (IG2 power supply input for entire steering lock actuator assembly)* Engine switch off --> engine switch on (IG) Below 1 V --> 11 to 14 V - K28-7 (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 (smart key ECU assembly) may store DTC B2786. NOTE: There is 1 motor and 2 sensors built into the steering lock actuator assembly. 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). To lock the steering, turn the engine switch off with the shift lever in P, and then open a door. Waveform *a Steering Lock Motor not Operating *b Steering Lock Motor Operating Item Content Tester Connection K28-3 (IGE) - K28-1 (GND) Tool Setting 2 V/DIV., 200 ms./DIV. Vehicle Condition Steering lock motor not operating --> Operating --> Not operating

DIAGNOSIS SYSTEM [04/2013 - ]

1. DESCRIPTION The steering lock ECU (steering lock actuator assembly) 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 and select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Access. 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 system. Be sure to confirm and record any DTCs output for other systems. The steering lock ECU (steering lock actuator assembly) is not connected to the CAN communication system. Therefore, communication with the Techstream is performed via the certification ECU (smart key ECU assembly). The steering lock ECU (steering lock actuator assembly) only stores DTCs for currently existing malfunctions. History DTCs are not stored.

DTC CHECK/CLEAR [04/2013 - ]

Note. The steering lock ECU (steering lock actuator assembly) does not store history 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 system. Be sure to confirm and record any DTCs output for other systems. When using the Techstream with the engine switch off, connect the Techstream to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Access. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.

1. CHECK FOR DTC (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 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 / Main Body / Trouble Codes. Body Electrical > Main Body > Trouble Codes Check for DTCs.
2. CHECK FOR DTC (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) HINT: The steering lock system DTCs are output from the steering lock ECU (steering lock actuator assembly) via the certification ECU (smart key ECU assembly). 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 / Smart Access / Trouble Codes. Body Electrical > Smart Access > Trouble Codes Check for DTCs.
3. CLEAR DTC (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 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 / Main Body / Trouble Codes. Body Electrical > Main Body > Clear DTCs Clear the DTCs.
4. CLEAR DTC (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 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 / Smart Access / Trouble Codes. Body Electrical > Smart Access > Clear DTCs Clear the DTCs.

Scheme 67

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 (steering lock actuator assembly) communicates with the Techstream through the certification ECU (smart key ECU assembly) which uses CAN communication. If the CAN communication system or certification ECU (smart key ECU assembly) is malfunctioning, Data List items may not be normal. When using the Techstream with the engine switch off, connect the Techstream to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Access. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle. Body Electrical > Power Source Control > Data List Tester Display Measurement Item Range Normal Condition Diagnostic Note Shift P Signal Shift position (P) signal 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 ECU (steering lock actuator assembly) ON or OFF ON: Steering unlocked OFF: Steering locked 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". Body Electrical > Smart Access > Data List Tester Display Measurement Item Range Normal Condition Diagnostic Note # Codes Number of trouble codes Min: 0 Max: 255 Number of stored DTCs displayed - Immobilizer State of immobilizer system determined by certification ECU (smart key ECU assembly) Set or Unset Set: Immobilizer set (engine start prohibited) (engine switch off) Unset: Immobilizer unset (engine start permitted) (engine switch on (ACC) or on (IG)) When the immobilizer cannot be unset, this item can be used to determine whether the certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is part of the problem. The engine cannot be started when this item displays "Set". HINT: The state of the immobilizer (whether it is set or unset) can be determined through the certification ECU (smart key ECU assembly). If this item displays "Set", the communication between the certification ECU (smart key ECU assembly) and ID code box (immobilizer code ECU) can be determined to be normal. The security indicator light operation is only linked with the state of the immobilizer (set/unset), and is not related to the steering lock operation (lock/unlock), when the immobilizer is set, the security indicator light blinks. Steering Lock Sleep Cond Steering lock ECU (steering lock actuator assembly) sleep availability Yes or No Yes: Sleep available No: Sleep not available - Steering Lock Start Cond Steering lock ECU (steering lock actuator assembly) wake up signal status Yes or No Yes: Wake up signal sent No: Wake up signal not sent - Engine Start Condition State of engine start permission signal determined by steering lock ECU (steering lock actuator assembly) sent to certification ECU (smart key ECU assembly) OK or NG OK: Engine start permitted NG: Engine start prohibited When this item displays "OK", the certification ECU (smart key ECU assembly) has received an unlock confirmation signal from the steering lock ECU (steering lock actuator assembly) and has permitted fuel injection and engine combustion. The engine cannot be started when this item displays "NG". Sensor Value Record of malfunction of lock or unlock sensor in steering lock ECU (steering lock actuator assembly) (DTC B2781 is output) OK or NG(Past) OK: No record of lock/unlock sensor malfunction in steering lock ECU (steering lock actuator assembly) NG(Past): Record of lock/unlock sensor in steering lock ECU (steering lock actuator assembly) turning ON at same time exists When this item displays "NG", the sensor inside the steering lock ECU (steering lock actuator assembly) may be malfunctioning, or there may be a mechanical malfunction. Power Supply Short Record of malfunction of signal sent to steering lock motor (steering lock actuator assembly) from certification ECU (smart key ECU assembly) (short circuit) (DTC B2782 is output) 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 certification ECU (smart key ECU assembly) and steering lock motor (steering lock actuator assembly). Motor Driver Short Record of malfunction of motor activation circuit in steering lock ECU (steering lock actuator assembly) (short circuit) (DTC B2781 is output) 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 ECU (steering lock actuator assembly) (short circuit). Lock/Unlock Receive Reception state of steering lock or unlock request signal from certification ECU (smart key ECU assembly) 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 - Engine Start Request Reception state of engine start permission signal determined by steering lock ECU (steering lock actuator assembly) sent to certification ECU (smart key ECU assembly) OK or NG OK: Receiving signal NG: Not receiving signal When this item displays "OK", the certification ECU (smart key ECU assembly) has received an unlock confirmation signal from the steering lock ECU (steering lock actuator assembly) 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 (smart key ECU assembly) and ID code box (immobilizer code ECU) OK or NG OK: Verification result normal NG: Verification result abnormal When a malfunction is present: The ID code for the certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is not registered or the certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) 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 (immobilizer code ECU) and steering lock ECU (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 (immobilizer code ECU) or steering lock ECU (steering lock actuator assembly) is not registered or the ID code box (immobilizer code ECU) or steering lock ECU (steering lock actuator assembly) 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 request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobilizer code ECU) HINT: The reception state is maintained for 10 seconds. When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG". OK or 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 (smart key ECU assembly) may be malfunctioning. Lock Request Receive Reception state of steering lock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobilizer code ECU) HINT: The reception state is maintained for 10 seconds. When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG". OK or 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 (smart key ECU assembly) may be malfunctioning. S Code Check(Past) Verification result between certification ECU (smart key ECU assembly) and ID code box (immobilizer code ECU) (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 (immobilizer code ECU) and steering lock ECU (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 (steering lock actuator assembly) 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 (steering lock actuator assembly) 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). Engine Start Indicator Smart warning light ON or OFF Customization status displayed - Open in IG2 History of IG2 input of the steering lock ECU (steering lock actuator assembly) OK or NG(Past) OK: History of open in IG2 exists NG(Past): No history of open in IG2 exists When OK is displayed, the steering lock ECU (steering lock actuator assembly) has an IG2 input circuit malfunction. 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 (smart key ECU assembly) 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 have elapsed 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 (smart key ECU assembly) are compared to check that they match. Certification ECU (smart key ECU assembly) 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 (immobilizer code ECU) uses the S code to determine whether the certification ECU (smart key ECU assembly) is authorized. The steering lock ECU (steering lock actuator assembly) uses the L code to determine whether the ID code box (immobilizer code ECU) is authorized. Lock operation conditions for the steering: When the following conditions are met and the certification ECU (smart key ECU assembly) 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 (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 changes to on (ACC). *2: Without depressing the brake pedal, press the engine switch and check that the power source mode changes to on (IG). *3: Press the engine switch and check that the power source mode changes to off. *4: Release the brake pedal, open the driver door and check that the steering locks. Body Electrical > Main Body > Data List Tester Display Measurement Item Range Normal Condition Diagnostic Note FL Door Courtesy SW Front door courtesy light switch assembly LH ON or OFF ON: Front door LH open OFF: Front door LH closed If this item does not change according to the actual state of the driver door, there is a malfunction in the door courtesy light switch or related part.
2. ACTIVE TEST HINT: Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests. 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) / Active Test. According to the display on the Techstream, perform the Active Test. Body Electrical > Power Source Control > Active Test Tester Display Measurement Item Control Range Diagnostic Note P Supply for Steering Lock Certification ECU (smart key ECU assembly) OFF/ON HINT: OFF: Power is not supplied ON: Power is supplied When performing this Active Test, make sure the following condition is met: The engine switch is on (IG).

DIAGNOSTIC TROUBLE CODE TABLE [04/2013 - ]

STEERING LOCK SYSTEM