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Steering Lock System (Diagnostics - Introduction): Diagnosis Lexus IS II facelift 2

Steering Column 3 illustrations ~1648 words

HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ]

HINT

*: Use the Techstream.

  1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
  2. CHECK AND CLEAR DTCS* NEXT: Go to next step
  3. PROBLEM SYMPTOM CONFIRMATION --> SYMPTOM DOES NOT OCCUR (Go to step 4) --> SYMPTOM OCCURS (Go to step 5)
  4. SYMPTOM SIMULATION NEXT: Go to next step
  5. CHECK MULTIPLEX COMMUNICATION SYSTEM HINT: Check that there are no problems in the multiplex communication system before troubleshooting the steering lock system. NEXT: Go to next step
  6. DTC CHECK* --> DTC IS NOT OUTPUT (Go to step 7) --> DTC IS OUTPUT (Go to step 8)
  7. PROBLEM SYMPTOMS TABLE --> Go to step 9
  8. DTC CHART NEXT: Go to next step
  9. CIRCUIT INSPECTION* NEXT: Go to next step
  10. PROBLEM IDENTIFICATION NEXT: Go to next step
  11. REPAIR OR REPLACEMENT NEXT: Go to next step
  12. CONFIRMATION TEST* NEXT --> END

PROBLEM SYMPTOMS TABLE [08/2012 - ]

Inspect the suspected areas in numerical order by referring to the corresponding Service Information when any of the following symptoms occurs

SymptomSuspected AreaSee Service Information
Steering wheel cannot be unlocked (the engine cannot be started).1. InitializationRefer to INITIALIZATION [08/2012 - ]
2. Check for DTCs in the push button start. (for 2GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
3. Check for DTCs in the push button start. (for 4GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
4. Check for DTCs in the engine immobiliser system.Refer to DTC CHECK / CLEAR [08/2012 - ]
5. Check that the Lock/Unlock Receive item in the DATA LIST of the certification ECU displays YES within 10 seconds after starting the engine. (If it displays NO, see No steering unlock command in this table.)Refer to DATA LIST / ACTIVE TEST [08/2012 - ]
6. Check the output from the IGE terminal of the steering lock ECU.Refer to Steering Lock Motor Drive Power Circuit
7. Steering lock ECU power source circuit.Refer to Power Source Circuit
8. Replace the steering lock ECU. (for Manual Tilt)Refer to DISASSEMBLY [08/2012 - ]
9. Replace the steering lock ECU. (for Power Tilt and Power Telescopic Steering)Refer to DISASSEMBLY [08/2012 - ]
Steering wheel cannot be unlocked (no steering unlock command).1. Check that the S Code Check 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 [08/2012 - ]
2. Check that the L Code Check 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 [08/2012 - ]
3. Replace the certification ECU.
Steering wheel cannot be locked.1. Check for DTCs in the push button start. (for 2GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
2. Check for DTCs in the push button start. (for 4GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
3. Check for DTCs in the engine immobiliser system.Refer to DTC CHECK / CLEAR [08/2012 - ]
4. With the engine switch off and the shift in the P position, open and close the drivers door. After that, check that the Lock/Unlock Receive 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 [08/2012 - ]
5. Check the output from the IGE terminal of the steering lock ECU.Refer to Steering Lock Motor Drive Power Circuit
6. Steering lock ECU power source circuit.Refer to Power Source Circuit
7. Replace the steering lock ECU. (for Manual Tilt)Refer to DISASSEMBLY [08/2012 - ]
8. Replace the steering lock ECU. (for Power Tilt and Power Telescopic)Refer to DISASSEMBLY [08/2012 - ]
Steering wheel cannot be locked (no steering lock command).1. Courtesy light switch circuitRefer to Door Courtesy Switch Circuit
2. Check that the S Code Check 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 [08/2012 - ]
3. Check that the L Code Check 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 [08/2012 - ]
4. Replace the certification ECU.

STEERING LOCK FUNCTION

SymptomSuspected AreaSee Service Information
Engine does not start.1. InitializationRefer to INITIALIZATION [08/2012 - ]
2. Check for DTCs in the push button start. (for 2GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
3. Check for DTCs in the push button start. (for 4GR-FSE)Refer to DTC CHECK / CLEAR [08/2012 - ]
4. Check for DTCs in the engine immobiliser system.Refer to DTC CHECK / CLEAR [08/2012 - ]
5. Check that the engine switch is turned on.
6. Check cranking operation. (If cranking operation is possible, see Engine does not start due to the engine immobilizer in this table.)
7. Check Shift P Sig in the DATA LIST of the power source control ECU and confirm that the shift signal is normal.
8. 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.)
9. Check the output from the SLP terminal of the steering lock ECU.Refer to Unlock Position Sensor Signal Circuit
10. Check the output signal from the ST SW of the certification ECU (DTC B2275). (for 2GR-FSE)Refer to DTC B2275: STSW Monitor Malfunction
11. Check the output signal from the ST SW of the certification ECU (DTC B2275). (for 4GR-FSE)Refer to DTC B2275: STSW Monitor Malfunction
12. Replace the power source control ECU.
Engine does not start due to the engine immobilizer.1. Check that the L Code Check 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 [08/2012 - ]
2. Check that the Engine Start Request 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 [08/2012 - ]
3. Check that the S Code Check 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 [08/2012 - ]
4. Replace the ID code box.

PUSH BUTTON START FUNCTION

Scheme 93

Scheme 93: TERMINALS OF ECU [08/2012 - ]
Scheme 93: TERMINALS OF ECU [08/2012 - ]
  1. STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition J29-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 V J29-2 (SGND) - Body ground W-B - Body ground Signal ground Always Below 1 V J29-3 (IGE) - J29-1 (GND) W - W-B Power source for driving motor Motor is in operation Motor is not in operation Below 1 V 10 to 12 V J29-4 (SLP1) - J29-2 (SGND) R - W-B Unlock position sensor output signal Steering is locked Steering lock is released 10 to 14 V Below 1 V J29-5 (LIN) - J29-2 (SGND) V - W-B LIN communication bus Engine switch on (IG) Pulse generation J29-6 (IG2) - J29-1 (GND) LG - W-B IG signal input Engine switch on (IG) 10 to 14 V J29-7 (B) - J29-1 (GND) G - W-B Power source Always 10 to 14 V

Scheme 94

Scheme 94: DIAGNOSIS SYSTEM [08/2012 - ]
Scheme 94: DIAGNOSIS SYSTEM [08/2012 - ]

Scheme 95

Scheme 95
Scheme 95
  1. DESCRIPTION DIAGNOSTIC SYSTEM When troubleshooting a vehicle with a diagnostic system, the only difference from the usual troubleshooting procedure is connecting the Techstream to the vehicle and reading various data output from the vehicle's steering lock ECU. The steering lock ECU records DTCs when the computer detects a malfunction in the computer itself or in its circuits. To check the DTCs, connect the Techstream to the DLC3 on the vehicle. The Techstream enables the DTCs to be cleared, the indicators to be activated, and the DATA LIST to be checked. The diagnosis information of the steering lock ECU is transmitted to the Techstream via the certification ECU as the steering lock ECU is not connected to BEAN. Check the DLC3. The certification ECU follows ISO 9141-2 for its communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format. Symbols (Terminals No.) Terminal Description Condition Specified Condition SIL (7) - SG (5) Bus "+" line During communication Pulse generation CG (4) - Body ground Chassis ground Always Below 1 ohms SG (5) - Body ground Signal ground Always Below 1 ohms BAT (16) - Body ground Battery positive Always 11 to 14 V HINT: If the display shows a communication error message after connecting the Techstream cable to the DLC3 and turning the engine switch on (IG), there is a problem with either the vehicle or Techstream. If communication is normal when connecting the Techstream to another vehicle, inspect the DLC3 on the original vehicle. If communication is still not possible when connecting the Techstream to another vehicle, the problem is probably on the Techstream itself. Consult the Service Department listed in the Techstream's operator's manual.
  2. WARNING FUNCTION OF ENGINE SWITCH INDICATOR The steering lock ECU blinks the LED indicator of the engine switch when any of the following problems occurs in the system: Detection Item Indicator Light Blink Pattern Indication Status Countermeasure Steering lock is still not released Blinks green at 1-second intervals Goes off 15 seconds after blinking starts The motor operates to release the steering lock, but the steering lock cannot be released (e.g. the lock bar is stuck in the steering column). Push the engine switch while turning the steering wheel left or right. Malfunction in push start system Blinks amber at 2-second intervals Goes off 15 seconds after the engine switch is turned off while blinking There is a short in the devices activating the motor. There is a problem in the steering lock ECU or power source control ECU. Troubleshoot by following "HOW TO PROCEED WITH TROUBLESHOOTING". Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ]»(ref-606505-S29571334362014032500000) for 4GR-FSE, or Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ]»(ref-606518-S32752482902014032500000) for 2GR-FSE).
  3. WARNING FUNCTION OF COMBINATION METER The steering lock ECU displays a warning on the combination meter when any of the following problems occurs in the system. Detection Item Display Indication Status Countermeasure Steering lock is still not released "S/T is not Unlocked" Goes off 15 seconds after blinking starts The motor operates to release the steering lock, but the steering lock cannot be released (e.g. the lock bar is stuck in the steering column). Push the engine switch while turning the steering wheel left or right. Malfunction in push start system "Check S/T Lock" Goes off 15 seconds after the engine switch is turned off while blinking There is a short in the devices activating the motor. There is a problem in the steering lock ECU or power source control ECU. Troubleshoot by following "HOW TO PROCEED WITH TROUBLESHOOTING". Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ]»(ref-606505-S29571334362014032500000) for 4GR-FSE, or Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ]»(ref-606518-S32752482902014032500000) for 2GR-FSE).

DTC CHECK / CLEAR [08/2012 - ]

  1. CHECK FOR DTCS Turn the engine switch off. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Check for DTCs. Enter the following menus: Body / Smart Access / Trouble Codes. Confirm the details of the DTCs. Refer to «DIAGNOSTIC TROUBLE CODE CHART [08/2012 - ]»(ref-606562-S11655974702014032500000) .
  2. CLEAR DTCS Turn the engine switch off. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Clear the DTCs. Enter the following menus: Body / Smart Access / Trouble Codes. According to the display on the Techstream, select the trouble code data display with the clear button.

DATA LIST / ACTIVE TEST [08/2012 - ]

  1. 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 / Smart Access / Data List. According to the display on the Techstream, read the Data List. SMART ACCESS Tester Display Measurement Item/Range Normal Condition Diagnostic Note Steering Lock Sleep Cond Steering lock ECU sleep condition / YES or NO YES: Steering lock ECU sleep mode can be entered NO: Steering lock ECU sleep mode cannot be entered - Steering Lock Start Cond Steering lock ECU start signal / YES or NO YES: Steering lock ECU sent a start signal NO: Steering lock ECU did not send a start signal - Engine Start Condition Engine start condition / OK or NG OK: Engine is allowed to start NG: Engine is not allowed to start - Sensor Value Sensor malfunction / NG (PAST) or OK NG (PAST): Sensor malfunction OK: No malfunction - Power Supply Short Short in ECU / NG (PAST) or OK NG (PAST): Short in ECU OK: No malfunction - Power Supply Open Open in ECU / NG (PAST) or OK NG (PAST): Open in ECU OK: No malfunction - Motor Driver Short Short in driver ECU / NG (PAST) or OK NG (PAST): Short in driver ECU OK: No malfunction - Motor Driver Open Open in driver ECU / NG (PAST) or OK NG (PAST): Open in driver ECU OK: No malfunction - Lock/Unlock Receive Steering lock command reception record / YES or NO YES: Steering lock / unlock signal received NO: Steering lock / unlock signal no received - Lock Bar Stuck Error Lock bar stuck malfunction / NG (PAST) or OK NG (PAST): Lock bar stuck malfunction OK: No malfunction - Push Start Error Push button start function malfunction / NG (PAST) or OK NG (PAST): Malfunction in push button start OK: No malfunction - IG2 Status IG2 voltage / OK or OFF ON: 10 to 14 V OFF: Below 1 V - IG(Lin) LIN bus start-up status / ON or OFF ON: LIN bus started-up OFF: LIN bus not started-up - Steering Lock Steering lock condition / Set or Unset Set: Steering lock is set Unset: Steering lock is not set This status changes depending on the state of various sensors Steering Unlock Steering unlock condition / Set or Unset Set: Steering unlock is set Unset: Steering unlock is not set This status changes depending on the state of various sensors

DIAGNOSTIC TROUBLE CODE CHART [08/2012 - ]

If a trouble code is displayed during the DTC check, check the parts listed for that code in the table below and proceed to the appropriate Service Information.

HINT

The steering lock ECU does not store DTCs regarding the past problems.

DTC CodeDetection ItemTrouble AreaSee Service Information
B2781Open / Short in Steering Lock ECUSteering lock actuator assembly (Steering lock ECU)Refer to DTC B2781: Open / Short in Steering Lock ECU
B2782Power Source Control ECU Malfunction1. Wire harness 2. Steering lock actuator assembly (Steering lock ECU) 3. Power source control ECURefer to DTC B2782: Power Source Control ECU Malfunction
B2788IG2 Signal Malfunction1. IG2 relay 2. Wire harness 3. Power source control ECU 4. Steering lock actuator assembly (Steering lock ECU)Refer to DTC B2788: IG2 Signal Malfunction

STEERING LOCK SYSTEM

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