Unable to Unlock Steering Wheel (Engine cannot Start): Procedure

1. Using the Techstream, confirm the output of DTCs for all systems.

   OK

   No DTCs are output.

   NOTE:

   • 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 Key. 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.
   • Make sure that no DTCs are output. If any DTCs are output, proceed to Diagnostic Trouble Code Chart. Refer to DIAGNOSTIC TROUBLE CODE CHART [05/2013 - ] .

NG → REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

OK: Go to next step 

1. Check the power source mode change.
   1. When the key is inside the vehicle and the shift lever in P*1, check that pressing the engine switch with the brake pedal*1 or clutch pedal*2 released causes the power source mode to change as follows:
      • *1: for Automatic Transmission
      • *2: for Manual Transmission

      OK

      Off → on (ACC) → on (IG) → off

NG → See step   16 

OK: Go to next step 

1. Use the Data List to check if the steering lock request is functioning properly.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Unlock Request Receive*1	Reception state of steering unlock command signal determined 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 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.
   Unlock Request Receive*2	Reception state of steering unlock command signal determined by certification ECU (smart key ECU assembly) / 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 (smart key ECU assembly) may be malfunctioning.

   • *1: w/ ID Code Box
   • *2: w/o ID Code Box

   OK

   Within 10 seconds of turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

   RESULT
   
   

   Result	Proceed to
   OK	A
   NG (w/o ID Code Box)	B
   NG (w/ ID Code Box)	C

B → See step   6 

C → See step   9 

A: Go to next step 

1. Disconnect the D59 steering lock actuator assembly (steering lock ECU) connector.
2. Measure the resistance and voltage according to the value(s) in the table below.
   Fig 1: D59 Steering Lock Actuator Assembly (Steering Lock ECU) Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D59-1 (GND) - Body ground	Always	Below 1 Ω

   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
   D59-7 (B) - Body ground	Always	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Steering Lock Actuator Assembly (Steering Lock ECU))

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the D59 steering lock actuator assembly (steering lock ECU) connector.
2. Check the signal waveform according to the condition(s) in the table below.
   Fig 2: D59 Steering Lock Actuator Assembly (Steering Lock ECU) Connector & Signal Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   STANDARD FREQUENCY
   
   

   Item	Content
   Tester Connection	D59-3 (SLR+) - D59-1 (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 Actuator Assembly (Steering Lock ECU))
   *b	Steering lock motor not operating
   *c	Steering lock motor operating

   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.
       • *: for Automatic Transmission

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   14 

1. Use the Data List to check if L code certification is functioning properly.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   L Code Check	Verification result between ID code box (immobilizer code ECU) 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 (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is not registered or the ID code box (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

   HINT: 

   Reasons for verification failure:

   • The steering lock actuator assembly (steering lock ECU) or ID code box (immobilizer code ECU) is malfunctioning.
   • There is a problem with the communication between ECUs.
   • An ECU is replaced, but is not registered.
   • An ECU is replaced with an ECU which has a code already stored in it.

NG → See step   8 

OK: Go to next step 

1. Replace the steering lock actuator assembly (steering lock ECU) with a new one. Refer to DISASSEMBLY [05/2013 - ] .
2. Perform registration. Refer to REGISTRATION [05/2013 - ] .
3. Turn the engine switch on (IG).
4. Turn the steering wheel and check the steering condition.

   OK

   Steering is unlocked.

NG → See step   15 

OK → END 

1. Replace the certification ECU (smart key ECU assembly) with a new one. Refer to REMOVAL [05/2013 - ] .
2. Perform registration. Refer to REGISTRATION [05/2013 - ] .
3. Use the Data List to check if L code certification is functioning properly again.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   L Code Check	Verification result between ID code box (immobilizer code ECU) 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 (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is not registered or the ID code box (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

NG → See step   14 

OK → END 

1. Use the Data List to check if S code certification is functioning properly.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   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 ID code box (immobilizer code ECU) or certification ECU (smart key ECU assembly) is not registered or the ID code box (immobilizer code ECU) or certification ECU (smart key ECU assembly) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

   HINT: 

   Reasons for verification failure:

   • The certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is malfunctioning.
   • There is a problem with the communication between ECUs.
   • An ECU is replaced, but is not registered.
   • An ECU is replaced with an ECU which has a code already stored in it.

NG → See step   12 

OK: Go to next step 

1. Use the Data List to check if L code certification is functioning properly.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   L Code Check	Verification result between ID code box (immobilizer code ECU) 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 (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is not registered or the ID code box (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

   HINT: 

   Reasons for verification failure:

   • The steering lock actuator assembly (steering lock ECU) or ID code box (immobilizer code ECU) is malfunctioning.
   • There is a problem with the communication between ECUs.
   • An ECU is replaced, but is not registered.
   • An ECU is replaced with an ECU which has a code already stored in it.

NG → See step   13 

OK: Go to next step 

1. Replace the steering lock actuator assembly (steering lock ECU) with a new one. Refer to DISASSEMBLY [05/2013 - ] .
2. Perform registration. Refer to REGISTRATION [05/2013 - ] .
3. Turn the engine switch on (IG).
4. Turn the steering wheel and check the steering condition.

   OK

   Steering is unlocked.

NG → See step   15 

OK → END 

1. Replace the certification ECU (smart key ECU assembly) with a new one. Refer to REMOVAL [05/2013 - ] .
2. Perform registration. Refer to REGISTRATION [05/2013 - ] .
3. Use the Data List to check if S code certification is functioning properly again.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   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 ID code box (immobilizer code ECU) or certification ECU (smart key ECU assembly) is not registered or the ID code box (immobilizer code ECU) or certification ECU (smart key ECU assembly) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

NG → See step   17 

OK → END 

1. Replace the steering lock actuator assembly (steering lock ECU) with a new one. Refer to DISASSEMBLY [05/2013 - ] .
2. Perform registration. Refer to REGISTRATION [05/2013 - ] .
3. Use the Data List to check if L code certification is functioning properly again.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   L Code Check	Verification result between ID code box (immobilizer code ECU) 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 (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is not registered or the ID code box (immobilizer code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

   OK

   OK is displayed on the Techstream.

NG → See step   17 

OK → END