STEERING LOCK SYSTEM Unable to Unlock Steering Wheel (Engine cannot Start)

DTC Code	DTC Name
	Unable to Unlock Steering Wheel (Engine cannot Start)

DESCRIPTION

The steering lock actuator assembly activates the steering lock motor and moves the lock bar into the steering column to lock the steering.

The steering may not unlock when the lock bar gets stuck in the lock hole of the steering column. In this case, if the engine switch is turned on (IG) while shaking the steering wheel, as is done for a vehicle with a mechanical key, the lock bar will be unlocked. If the certification ECU (smart key ECU assembly), ID code box (immobiliser code ECU) (for RHD) or ECM is replaced, the system needs to be initialized. Otherwise, the steering cannot be unlocked and the engine cannot be started.

Table 1. Related Data List and Active Test Items
Problem Symptom	Data List Item	Active Test Item
Unable to unlock steering wheel (Engine cannot start)	Entry&Start Unlock Request Receive S Code Check (for RHD) Steering Unlock L Code Check	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

Note:

When using the GTS with the engine switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
Perform either of the following operations to lock/unlock the steering:
- 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 N*, and then open a door.
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.
Click here
After performing repairs, confirm that the problem does not recur.
Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart.
Click here
Inspect the fuses for circuits related to this system before performing the following procedure.
When replacing the steering lock ECU (steering lock actuator assembly), certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) (for RHD), registration must be performed (refer to Service Bulletin).
When disconnecting the cable from the negative (-) battery terminal, some systems need to be initialized after the cable is reconnected.
Click here Click here Click here
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 engine. This function prevents the engine from starting while the steering is locked. If the steering is locked for any reason, open and close a door with the engine switch off, and then unlock the steering by pressing the engine switch.
- *: for Multi-Mode Manual Transaxle

PROCEDURE

CHECK ENGINE SWITCH (SWITCH CONDITION)

Check the power source mode change.
1. When the key is inside the vehicle and the shift lever is in N*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:
  
  OK
  
  Off → On (ACC) → On (IG) → Off
  
  *1: for Multi-Mode Manual Transaxle
  *2: for Manual Transaxle

Result


Proceed to
OK
NG

GO TO ENTRY AND START SYSTEM (for Start Function) (PROBLEM SYMPTOMS TABLE)

Click here

CHECK SMART WARNING LIGHT

Turn the engine switch on (IG).
Check that the smart warning light on the combination meter assembly is rapidly blinking green.

Result


Result	Proceed to
Smart warning light is blinking rapidly.	A
Smart warning light is not blinking rapidly.	B

CHECK FOR DTCClick here

CHECK STEERING UNLOCK CONDITION

While turning the steering wheel left and right, press the engine switch.
Check that the steering is unlocked.

Result


Result	Proceed to
The steering is unlocked.	A
The steering is not unlocked.	B

END

CHECK FOR DTC

Using the GTS, check if certification ECU (smart key ECU assembly) DTCs are output.
Click here

Body Electrical > Entry&Start > Trouble Codes

Result


Result	Proceed to
DTCs are not output.	A
DTCs are output.	B

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

READ VALUE USING GTS (UNLOCK REQUEST RECEIVE)

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

Body Electrical > Entry&Start > Data List


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) sent to ID code box (immobiliser code ECU)1 Reception state of steering unlock request signal by certification ECU (smart key ECU assembly)2 Tip: 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.

Body Electrical > Entry&Start > Data List


Tester Display
Unlock Request Receive

*1: for RHD
*2: for LHD

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 (for RHD)	A
OK (for LHD)	B
NG	C

READ VALUE USING GTS (L CODE CHECK)Click here

INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)Click here

READ VALUE USING GTS (S CODE CHECK)

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

Body Electrical > Entry&Start > Data List


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 (immobiliser 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 (immobiliser code ECU) is not registered or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Entry&Start > Data List


Tester Display
S Code Check

OK is displayed on the GTS.

Tip:

Reasons for verification failure:

The certification ECU (smart key ECU assembly) or ID code box (immobiliser 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.

Result


Proceed to
OK
NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)Click here

READ VALUE USING GTS (L CODE CHECK)

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

Body Electrical > Entry&Start > Data List


Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
L Code Check	Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly)1 Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator assembly)2	OK or NG	OK: Verification result normal NG: Verification result abnormal	When a malfunction is present: The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.1 The ID code for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly) is not registered or the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly) is malfunctioning.2 The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Entry&Start > Data List


Tester Display
L Code Check

*1: for RHD
*2: for LHD

OK is displayed on the GTS.

Tip:

Reasons for verification failure:

The steering lock ECU (steering lock actuator assembly) or ID code box (immobiliser 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.

Result


Proceed to
OK
NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)Click here

CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

Disconnect the E47 steering lock ECU (steering lock actuator assembly) connector.

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

Measure the resistance and voltage according to the value(s) in the table below.

Standard Resistance


Tester Connection	Condition	Specified Condition
E47-1 (GND) - Body ground	Always	Below 1 Ω

Note:

If the result is not as specified, check for looseness in the ground cable connection.

Standard Voltage


Tester Connection	Condition	Specified Condition
E47-7 (B) - Body ground	Always	11 to 14 V

Result


Proceed to
OK
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Reconnect the E47 steering lock ECU (steering lock actuator assembly) connector.

*a	Component with harness connected (Steering Lock ECU (Steering Lock Actuator Assembly))
*b	Steering Lock Motor not Operating
*c	Steering Lock Motor Operating

Check the signal waveform according to the condition(s) in the table below.

Standard Frequency


Item	Content
Tester Connection	E47-3 (IGE) - E47-1 (GND)
Tool Setting	2 V/DIV., 200 ms./DIV.
Vehicle Condition	Steering lock motor not operating → Operating → Not operating

Tip:

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 N*, and then open a door.
- - *: for Multi-Mode Manual Transaxle

Result


Proceed to
OK
NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Click here

CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the E47 steering lock ECU (steering lock actuator assembly) connector.
Disconnect the E49 certification ECU (smart key ECU assembly) 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
E47-3 (IGE) - E49-17 (SLR+)	Always	Below 1 Ω
E47-3 (IGE) or E49-17 (SLR+) - Body ground	Always	10 kΩ or higher

Result


Proceed to
OK
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Reconnect the E47 steering lock ECU (steering lock actuator assembly) connector.
Reconnect the E49 certification ECU (smart key ECU assembly) connector.

*a	Component with harness connected (Steering Lock ECU (Steering Lock Actuator Assembly))

Measure the voltage according to the value(s) in the table below.

Standard Voltage


Tester Connection	Condition	Specified Condition
E47-3 (IGE) - Body ground	Always	11 to 14 V

Result


Proceed to
OK
NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Click here

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Replace the steering lock ECU (steering lock actuator assembly) with a new one.
Click here
Perform registration (refer to Service Bulletin).
Turn the engine switch on (IG).

Use the Data List to check if L code certification is functioning properly again.

Body Electrical > Entry&Start > Data List


Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
L Code Check	Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly)1 Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator assembly)2	OK or NG	OK: Verification result normal NG: Verification result abnormal	When a malfunction is present: The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.1 The ID code for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly) is not registered or the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly) is malfunctioning.2 The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Entry&Start > Data List


Tester Display
L Code Check

*1: for RHD
*2: for LHD

OK is displayed on the GTS.

Result


Result	Proceed to
OK	A
NG (for RHD)	B
NG (for LHD)	C

END

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

Replace the certification ECU (smart key ECU assembly) with a new one.
Perform registration (refer to Service Bulletin).

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

Body Electrical > Entry&Start > Data List


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 (immobiliser 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 (immobiliser code ECU) is not registered or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning. The steering cannot be locked. The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Entry&Start > Data List


Tester Display
S Code Check

OK is displayed on the GTS.

Result


Proceed to
OK
NG

END

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Measure the voltage according to the value(s) in the table below.

Standard Voltage


Tester Connection	Condition	Specified Condition
E47-4 (SLP1) - Body ground	Always	11 to 14 V

Result


Proceed to
OK
NG

CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))Click here

READ VALUE USING GTS (STEERING UNLOCK)

Check that the steering is locked.

Read the Data List according to the display on the GTS.

Body Electrical > Entry&Start > Data List


Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
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).

Body Electrical > Entry&Start > Data List


Tester Display
Steering Unlock

OK is displayed on the GTS.

Result


Proceed to
OK
NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

Click here

READ VALUE USING GTS (UNLOCK REQUEST RECEIVE)

Replace the certification ECU (smart key ECU assembly) with a new one.
Perform registration (refer to Service Bulletin).
Turn the engine switch on (IG).

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

Body Electrical > Entry&Start > Data List


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) sent to ID code box (immobiliser code ECU)1 Reception state of steering unlock request signal by certification ECU (smart key ECU assembly)2 Tip: 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.

Body Electrical > Entry&Start > Data List


Tester Display
Unlock Request Receive

*1: for RHD
*2: for LHD

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 (for RHD)	B
NG (for LHD)	C

END

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the E47 steering lock ECU (steering lock actuator assembly) connector.
Disconnect the E49 certification ECU (smart key ECU assembly) 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
E47-4 (SLP1) - E49-22 (SLP)	Always	Below 1 Ω
E47-4 (SLP1) or E49-22 (SLP) - Body ground	Always	10 kΩ or higher

Result


Proceed to
OK
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

READ VALUE USING GTS (UNLOCK REQUEST RECEIVE)

Replace the steering lock ECU (steering lock actuator assembly) with a new one.
Perform registration (refer to Service Bulletin).
Turn the engine switch on (IG).

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

Body Electrical > Entry&Start > Data List


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) sent to ID code box (immobiliser code ECU)1 Reception state of steering unlock request signal by certification ECU (smart key ECU assembly)2 Tip: 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.

Body Electrical > Entry&Start > Data List


Tester Display
Unlock Request Receive

*1: for RHD
*2: for LHD

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


Proceed to
OK
NG

END

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)