Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000001QT51
Model Year Start: 2021 Model: RAV4 Prod Date Range: [08/2020 - 12/2021]
Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): Unable to Unlock Steering Wheel (Engine cannot Start); 2021 MY RAV4 [08/2020 - 12/2021]

Unable to Unlock Steering Wheel (Engine cannot Start)

DESCRIPTION

The steering lock ECU (steering lock actuator with ECU 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), ECM is replaced, the system needs to be initialized. Otherwise, the steering cannot be unlocked and the engine cannot be started.

Related Data List and Active Test Items

Problem Symptom

Data List and Active Test

Unable to unlock steering wheel (Engine cannot start)

Smart Key

  • Unlock Request Receive
  • L Code Check
  • Steering Unlock

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off, connect the Techstream to the DLC3 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.
  • The smart key system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.

    Click here 2021 MY RAV4 [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING

  • After completing repairs, confirm that the problem does not recur.
  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
  • Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart.
  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the steering lock ECU (steering lock actuator with ECU assembly), certification ECU (smart key ECU assembly), refer to the Registration.

    Click here 2021 MY RAV4 [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

PROCEDURE

1.

CHECK POWER SOURCE MODE CHANGING FUNCTION (SWITCH CONDITION)

(a) Check the power source mode change.

Click here 2019 - 2021 MY RAV4 [11/2018 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): OPERATION CHECK

OK:

The power source mode changes to on (IG).

NG

GO TO SMART KEY SYSTEM (for Start Function) (Power Source Mode does not Change to ON (IG and ACC))

OK

2.

CHECK INDICATOR

(a) With the engine switch on (IG), check that push engine switch while turning steering wheel in either direction is displayed on the multi-information display in the combination meter assembly.

Result

Proceed to

Push engine switch while turning steering wheel in either direction is displayed.

A

Push engine switch while turning steering wheel in either direction is not displayed.

B
B

GO TO STEP 4

A

3.

CHECK STEERING UNLOCK

(a) Turn the steering wheel left and right, and then press the engine switch.

(b) Check that the steering is unlocked.

Result

Proceed to

The steering is unlocked.

A

The steering is not unlocked.

B
A

END (STEERING LOCK IS NORMAL)
B

4.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Smart Key / Trouble Codes.

(e) Check for DTCs and note any DTCs that are output.

Body Electrical > Smart Key > Trouble Codes

Body Electrical > Power Source Control > Trouble Codes

Result

Proceed to

DTCs are not output.

A

DTCs are output.

B
B

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC

A

5.

READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE)

(a) Enter the following menus: Body Electrical / Smart Key / Data List.

(b) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Unlock Request Receive

Status of steering unlock command from certification ECU (smart key ECU assembly)

OK or NG

OK: Unlock request signal received within 10 seconds of engine switch being turned on (IG) or on (ACC) or of an engine start operation being performed

NG: Engine switch not turned on (IG) or on (ACC) and engine start operation not being performed
  • The engine cannot be started when an unlock request signal cannot be received.
  • If OK is not displayed even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

Body Electrical > Smart Key > Data List

Tester Display

Unlock Request Receive

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".

NG

GO TO STEP 12

OK

6.

READ VALUE USING TECHSTREAM (L CODE CHECK)

(a) Enter the following menus: Body Electrical / Smart Key / Data List.

(b) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

L Code Check

Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator with ECU assembly)

OK or NG

OK: Verification result normal

NG: Verification result abnormal

When NG is displayed:

  • The ID code for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator with ECU assembly) is not registered, or the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator with ECU assembly) is malfunctioning.
  • The steering cannot be locked.
  • The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Smart Key > Data List

Tester Display

L Code Check

OK:

OK is displayed on the Techstream.

HINT:

Reasons for verification failure:

  • The steering lock ECU (steering lock actuator with ECU assembly) or certification ECU (smart key ECU assembly) 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

GO TO STEP 11

OK

7.

CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) - POWER SUPPLY AND BODY GROUND)

(a) Disconnect the steering lock ECU (steering lock actuator with ECU assembly) connector.

*a

Front view of wire harness connector

(to Steering Lock ECU (Steering Lock Actuator with ECU Assembly))

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G56-1 (GND) - Body ground

Always

Below 1 Ω

NOTICE:

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

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

G56-7 (B) - Body ground

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

8.

CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) (MOTOR ACTIVATION COMMAND SIGNAL)

(a) Reconnect the steering lock ECU (steering lock actuator with ECU assembly) connector.

(b) Using an oscilloscope, check the waveform.

OK:

Tester Connection

Tool Setting

Condition

Specified Condition

G56-3 (IGE) - G56-1 (GND)

2 V/DIV., 200 ms./DIV.

Any door opened when following conditions are met, and then steering lock motor activated:

  • Shift state park (P)
  • Steering lock unlocked in advance by carrying key and turning engine switch on (IG)
  • After above conditions are met, engine switch turned off

Pulse generation

(See waveform)

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 state park (P), and then open a door.

*a

Component with harness connected

(Steering Lock ECU (Steering Lock Actuator with ECU Assembly))

*b

Steering Lock Motor not Operating

*c

Steering Lock Motor Operating

*d

Waveform
OK

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

NG

9.

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

(a) Disconnect the G56 steering lock ECU (steering lock actuator with ECU assembly) connector.

(b) Disconnect the G54 certification ECU (smart key ECU assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G56-3 (IGE) - G54-25 (SLR+)

Always

Below 1 Ω

G56-3 (IGE) or G54-25 (SLR+) - Other terminals and body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

10.

CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

(a) Reconnect the steering lock ECU (steering lock actuator with ECU assembly) connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

G56-3 (IGE) - Body ground

Always

11 to 14 V

*a

Component with harness connected

(Steering Lock ECU (Steering Lock Actuator with ECU Assembly))
OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

11.

CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

(a) Replace the steering lock ECU (steering lock actuator with ECU assembly) with a new one and perform registration again.

Click here 2019 - 2021 MY RAV4 RAV4 HV [11/2018 - 12/2021]; STEERING COLUMN: STEERING COLUMN ASSEMBLY: DISASSEMBLY

HINT:

Refer to Registration.

Click here 2021 MY RAV4 [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

(b) Enter the following menus: Body Electrical / Smart Key / Data List.

(c) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

L Code Check

Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator with ECU assembly)

OK or NG

OK: Verification result normal

NG: Verification result abnormal

When NG is displayed:

  • The ID code for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator with ECU assembly) is not registered, or the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator with ECU assembly) is malfunctioning.
  • The steering cannot be locked.
  • The steering cannot be unlocked (the engine cannot be started).

Body Electrical > Smart Key > Data List

Tester Display

L Code Check

OK:

OK is displayed on the Techstream.

OK

END (STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) WAS DEFECTIVE)
NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

12.

CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

G56-4 (SLP1) - Body ground

Always

11 to 14 V

*a

Component with harness connected

(Steering Lock ECU (Steering Lock Actuator with ECU Assembly))
NG

GO TO STEP 15

OK

13.

READ VALUE USING TECHSTREAM (STEERING UNLOCK)

(a) Check that the steering is locked.

(b) Enter the following menus: Body Electrical / Smart Key / Data List.

(c) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Steering Unlock

Steering lock ECU (steering lock actuator with ECU assembly) unlock confirmation status

Unset or Set

Unset: Unlock not confirmed

Set: Unlock confirmed

When Unset is displayed, the steering is not unlocked (the engine cannot be started).

Body Electrical > Smart Key > Data List

Tester Display

Steering Unlock

OK:

Set is displayed on the Techstream.

NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

OK

14.

READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE)

(a) Replace the certification ECU (smart key ECU assembly) with a new one.

Click here 2021 MY RAV4 RAV4 HV [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: CERTIFICATION ECU: REMOVAL

(b) Perform registration.

HINT:

Refer to Registration.

Click here 2021 MY RAV4 [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

(c) Enter the following menus: Body Electrical / Smart Key / Data List.

(d) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Unlock Request Receive

Status of steering unlock command from certification ECU (smart key ECU assembly)

OK or NG

OK: Unlock request signal received within 10 seconds of engine switch being turned on (IG) or on (ACC) or of an engine start operation being performed

NG: Engine switch not turned on (IG) or on (ACC) and engine start operation not being performed
  • The engine cannot be started when an unlock request signal cannot be received.
  • If OK is not displayed even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

Body Electrical > Smart Key > Data List

Tester Display

Unlock Request Receive

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".

OK

END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE)
NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY)

15.

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

(a) Disconnect the G56 steering lock ECU (steering lock actuator with ECU assembly) connector.

(b) Disconnect the G54 certification ECU (smart key ECU assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G56-4 (SLP1) - G54-14 (SLP)

Always

Below 1 Ω

G56-4 (SLP1) or G54-14 (SLP) - Other terminals and body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

16.

READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE)

(a) Replace the steering lock ECU (steering lock actuator with ECU assembly) with a new one.

Click here 2019 - 2021 MY RAV4 RAV4 HV [11/2018 - 12/2021]; STEERING COLUMN: STEERING COLUMN ASSEMBLY: DISASSEMBLY

(b) Perform registration.

HINT:

Refer to Registration.

Click here 2021 MY RAV4 [08/2020 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

(c) Enter the following menus: Body Electrical / Smart Key / Data List.

(d) Read the Data List according to the display on the Techstream.

Body Electrical > Smart Key > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Unlock Request Receive

Status of steering unlock command from certification ECU (smart key ECU assembly)

OK or NG

OK: Unlock request signal received within 10 seconds of engine switch being turned on (IG) or on (ACC) or of an engine start operation being performed

NG: Engine switch not turned on (IG) or on (ACC) and engine start operation not being performed
  • The engine cannot be started when an unlock request signal cannot be received.
  • If OK is not displayed even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

Body Electrical > Smart Key > Data List

Tester Display

Unlock Request Receive

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".

OK

END (STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) WAS DEFECTIVE)
NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)