Steering Lock System (Diagnostic Codes & Symptom Tests): Diagnosis Lexus GS IV

INSPECTION PROCEDURE

Note. When using the Techstream with the power switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins. After performing repairs, confirm that no DTCs are output again. Refer to DTC CHECK / CLEAR [03/2012 - ] . When replacing the steering lock ECU (steering lock actuator assembly), registration must be performed. Refer to REGISTRATION [03/2012 - ] .

HINT

When all the ECUs that are connected to the LIN communication cannot communicate with the certification ECU (smart key ECU assembly), DTC B2785 is stored.

Note. When using the Techstream with the power switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins. The steering lock system uses LIN communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ] . When disconnecting the cable from the negative (-) auxiliary battery terminal, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] . After performing repairs, perform the DTC output confirmation operation, and then confirm that no DTCs are output again. Refer to DTC CHECK / CLEAR [03/2012 - ] . When replacing the steering lock ECU (steering lock actuator assembly) or power management control ECU, registration must be performed. Refer to REGISTRATION [03/2012 - ] .

Scheme 66

1. INSPECT STEERING LOCK ECU (MOTOR ACTIVATION COMMAND SIGNAL) Make sure that there is no looseness at the locking part and the connecting part of the connector. Disconnect the steering lock ECU connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition N24-1 (GND) - Body ground Always Below 1 ohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Steering Lock ECU (Steering Lock Actuator Assembly)) Reconnect the steering lock ECU connector. Turn the power switch off, make sure that the steering is unlocked and move the shift lever to P. Check the signal waveform according to the condition(s) in the table below. STANDARD FREQUENCY Item Content Tester Connection N24-3 (IGE) - N24-1 (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 Component with harness connected (Steering Lock ECU (Steering Lock Actuator Assembly)) *b Steering lock motor not operating *c Steering lock motor operating HINT: When taking measurements while 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 power switch on (ACC) or on (IG) with the shift lever in P. To lock the steering, turn the power switch off and open or close a door with the shift lever in P. NG --> See step 4 OK: Go to next step
2. CLEAR DTC AND DATA LIST MALFUNCTION RECORD Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600648-S04285943142014022400000) . Disconnect the cable from the negative (-) auxiliary battery terminal, wait for 30 seconds or more, and then reconnect the cable to the negative (-) auxiliary battery terminal to clear the record of malfunctions stored in the Data List. WARNING: After turning the power switch off, waiting time may be required before disconnecting the cable from the auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the auxiliary battery terminal notices before proceeding with work. Refer to «PRECAUTION [03/2012 - ]»(ref-600412-S33693534232014022400000) . NEXT: Go to next step
3. READ VALUE USING TECHSTREAM (POWER SUPPLY SHORT) Perform the DTC output confirmation operation. Check if DTC B2782 is output. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600648-S04285943142014022400000) . Result Result Proceed to DTC B2782 is not output. A DTC B2782 is output. B B --> See step 5 A --> SYSTEM RETURNED TO NORMAL (DTC STORED DUE TO BAD CONNECTION, BUT SYSTEM RETURNED TO NORMAL BY RECONNECTING CONNECTOR)
4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - POWER MANAGEMENT CONTROL ECU) Make sure that there is no looseness at the locking part and the connecting part of the connectors. Disconnect the N24 steering lock ECU connector. Disconnect the N92 power management control ECU connector. Check for deformation and corrosion of the connector case and terminals. OK There is no deformation or corrosion of the connector case or terminals. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition N24-3 (IGE) - N92-6 (SLR+) Always Below 1 ohms N24-3 (IGE) - Body ground Always 10 kohms or higher N92-6 (SLR+) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 6
5. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to «DISASSEMBLY [03/2012 - ]»(ref-600607-S17635330842014022400000)
6. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to «REMOVAL [03/2012 - ]»(ref-600595-S22014970062014022400000)

Note. When using the Techstream with the power switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins. The steering lock system uses LIN communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ] . Inspect the fuses for circuits related to this system before performing the following inspection procedure. After performing repairs, confirm that no DTCs are output again. Refer to DTC CHECK / CLEAR [03/2012 - ] . When replacing the steering lock ECU (steering lock actuator assembly), registration must be performed. Refer to REGISTRATION [03/2012 - ] .

Scheme 67

1. INSPECT STEERING LOCK ECU (POWER SOURCE MODE SIGNAL) Make sure that there is no looseness at the locking part and the connecting part of the connector. Disconnect the steering lock ECU connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition N24-1 (GND) - Body ground Always Below 1 ohms TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Steering Lock ECU (Steering Lock Actuator Assembly)) Reconnect the steering lock ECU connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition N24-6 (IG2) - N24-1 (GND) Power switch on (IG) 11 to 14 V N24-6 (IG2) - N24-1 (GND) Power switch off Below 1 V TEXT IN ILLUSTRATION *a Component with harness connected (Steering Lock ECU (Steering Lock Actuator Assembly)) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 2
2. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to «DISASSEMBLY [03/2012 - ]»(ref-600607-S17635330842014022400000)

Note. When using the Techstream with the power switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins. Perform either of the following operations to lock/unlock the steering: To unlock the steering, carry the key and turn the power switch on (ACC) or on (IG) with the shift lever in P. To lock the steering, turn the power switch off and open or close a door with the shift lever in P. The steering lock system uses LIN communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ] . After performing repairs, confirm that the problem does not occur. Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart. Refer to DIAGNOSTIC TROUBLE CODE CHART [03/2012 - ] . Inspect the fuses for circuits related to this system before performing the following inspection procedure. When replacing the steering lock ECU (steering lock actuator assembly), certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU), registration must be performed. Refer to REGISTRATION [03/2012 - ] . If the steering lock ECU (steering lock actuator assembly) is replaced, be sure to confirm that the steering is unlocked by turning the steering wheel to the left and right before starting the hybrid control system. If the steering is locked for any reason, open and close a door with the power switch off, and then unlock the steering by pressing the power switch. This prevents the hybrid control system from starting while the steering is locked. When starting the hybrid control system, make sure that the shift lever is in P and that the shift lever is not tilted.

Scheme 68

1. CHECK DTC (ALL) See step 1 NG --> REPAIR CIRCUITS INDICATED BY OUTPUT DTCS OK: Go to next step
2. CHECK POWER SWITCH (SWITCH CONDITION) Check the power source mode change. When the key is inside the vehicle and the shift lever is in P, check that pressing the power switch with the brake pedal released causes the power source mode to change as follows: OK Off --> on (ACC) --> on (IG) --> off NG --> See step 12 OK: Go to next step
3. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) Use the Data List to check if the steering lock request is functioning properly. SMART ACCESS Tester Display Measurement Item/Range Normal Condition Diagnostic Note Unlock Request Receive Reception state of steering unlock request signal by certification ECU (smart key ECU assembly) and sent to ID code box (immobilizer code 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 power switch on (IG) or on (ACC) or starting hybrid control system NG: Except above If the unlock signal has not been received, the hybrid control system 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. OK Within 10 seconds of turning the power switch on (ACC) or on (IG) or starting the hybrid control system, the Data List item changes to "OK". NG --> See step 6 OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) Disconnect the steering lock ECU connector. Measure the resistance and voltage according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition N24-1 (GND) - Body ground Always Below 1 ohms NOTE: If the result is not as specified, check for looseness in the connection which leads to ground. Standard Voltage Tester Connection Condition Specified Condition N24-7 (B) - Body ground Always 11 to 14 V TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Steering Lock ECU (Steering Lock Actuator Assembly)) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
5. INSPECT STEERING LOCK ECU (MOTOR ACTIVATION COMMAND SIGNAL) Reconnect the steering lock ECU connector. Check the signal waveform according to the condition(s) in the table below. STANDARD FREQUENCY Item Content Tester Connection N24-3 (IGE) - N24-1 (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 Component with harness connected (Steering Lock ECU (Steering Lock Actuator Assembly)) *b Steering lock motor not operating *c Steering lock motor operating HINT: When taking measurements while 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 power switch on (ACC) or on (IG) with the shift lever in P. To lock the steering, turn the power switch off and open or close a door with the shift lever in P. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 14
6. READ VALUE USING TECHSTREAM (S CODE CHECK) See step 6 NG --> See step 9 OK: Go to next step
7. READ VALUE USING TECHSTREAM (L CODE CHECK) See step 7 NG --> See step 10 OK: Go to next step
8. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) See step 8 NG --> See step 11 OK --> END
9. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) See step 9 NG --> See step 13 OK --> END
10. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) See step 10 NG --> See step 15 OK --> END
11. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to «REMOVAL [03/2012 - ]»(ref-600642-S00554550882014022400000)
12. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (PROBLEM SYMPTOMS TABLE). Refer to «PROBLEM SYMPTOMS TABLE [03/2012 - ]»(ref-600421-S39785111942014022400000)
13. REPLACE ID CODE BOX (IMMOBILIZER CODE ECU). Refer to «REMOVAL [03/2012 - ]»(ref-600642-S19370879682014022400000)
14. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to «DISASSEMBLY [03/2012 - ]»(ref-600607-S17635330842014022400000)
15. REPLACE ID CODE BOX (IMMOBILIZER CODE ECU). Refer to «REMOVAL [03/2012 - ]»(ref-600642-S19370879682014022400000)

Note. When using the Techstream with the power switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins. Perform either of the following operations to lock/unlock the steering: To unlock the steering, carry the key and turn the power switch on (ACC) or on (IG) with the shift lever in P. To lock the steering, turn the power switch off and open or close a door with the shift lever in P. Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart. Refer to DIAGNOSTIC TROUBLE CODE CHART [03/2012 - ] . The steering lock system uses LIN communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ] . When replacing the steering lock ECU (steering lock actuator assembly), certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU), registration must be performed. Refer to REGISTRATION [03/2012 - ] . After performing repairs, confirm that the problem does not occur. If the steering lock actuator is replaced, before activating the hybrid control system, always turn the steering wheel to the right and left, etc. to confirm that the steering is unlocked. If the steering wheel is locked, perform an operation to lock the steering (open or close a door with the power switch off), and then perform an unlock operation (push the power switch). This prevents the hybrid control system from activating with the steering locked.