Smart Key
- Unlock Request Receive
- S Code Check
- L Code Check
- Steering Unlock
| Last Modified: 07-31-2024 | 6.11:8.1.0 | Doc ID: RM100000001H8E3 |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): Unable to Unlock Steering Wheel (Hybrid Control System cannot Start); 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022] | ||
|
Unable to Unlock Steering Wheel (Hybrid Control System cannot Start) |
DESCRIPTION
The steering lock ECU (steering lock actuator or upper bracket 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 power 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 ID code box (immobiliser code ECU) or hybrid vehicle control ECU is replaced, the system needs to be initialized. Otherwise, the steering cannot be unlocked and the hybrid control system cannot be started.
Related Data List and Active Test Items
|
Problem Symptom |
Data List and Active Test |
|---|---|
|
Unable to unlock steering wheel (Hybrid control system cannot start) |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- When using the Techstream with the power 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.
-
Perform either of the following operations to lock/unlock the steering:
- To unlock the steering, carry the electrical key transmitter sub-assembly and turn the power switch on (ACC) or on (IG).
- To lock the steering, turn the power switch off with the shift lever in P, and then open a door.
-
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
![2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
- After performing repairs, confirm that the problem does not recur.
- Make sure that no DTCs are output. If any DTCs are output, proceed to 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 or upper bracket assembly), ID code box (immobiliser code ECU) or certification ECU (smart key ECU assembly), refer to Registration.
Click here
-
When disconnecting the cable from the negative (-) auxiliary battery terminal, some systems need to be initialized after the cable is reconnected.
Click here
- If the steering lock ECU (steering lock actuator or upper bracket 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. This function prevents the hybrid control system from starting while the steering is locked. 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.
PROCEDURE
|
1. |
CHECK POWER SWITCH (SWITCH CONDITION) |
(a) Check the power source mode change.
(1) When the electrical key transmitter sub-assembly 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 |
|
GO TO OTHER PROBLEM
|
|
|
2. |
CHECK INDICATOR |
(a) With the power switch on (IG), check that Steering Lock active is displayed on the multi-information display in the combination meter assembly.
|
Result |
Proceed to |
|---|---|
|
Steering Lock active is displayed |
A |
|
Steering Lock active is not displayed |
B |
| B |
|
|
|
3. |
CHECK STEERING UNLOCK |
(a) Turn the steering wheel left and right, and then press the power switch.
(b) Check that the steering is unlocked.
|
Result |
Proceed to |
|---|---|
|
The steering is unlocked |
A |
|
The steering is not unlocked |
B |
| A |
|
|
|
4. |
READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Smart Key / Data List.
(e) 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: Certification ECU (smart key ECU assembly) sends steering unlock command (within 10 seconds of power switch turned on (ACC) or on (IG), or of hybrid control system start operation performed) NG: Certification ECU (smart key ECU assembly) does not send steering unlock command (power switch not turned on (ACC) or on (IG), and hybrid control system start operation not performed) |
|
Body Electrical > Smart Key > Data List
|
Tester Display |
|---|
|
Unlock Request Receive |
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 |
|
|
|
5. |
READ VALUE USING TECHSTREAM (S CODE CHECK) |
(a) 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 |
|---|---|---|---|---|
|
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 NG is displayed:
|
Body Electrical > Smart Key > Data List
|
Tester Display |
|---|
|
S Code Check |
OK:
OK is displayed on the Techstream.
HINT:
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 was replaced, but not registered.
- An ECU was replaced with an ECU which has already been registered to another vehicle.
| NG |
|
|
|
6. |
READ VALUE USING TECHSTREAM (L CODE CHECK) |
(a) 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 or upper bracket assembly) |
OK or NG |
OK: Verification result normal NG: Verification result abnormal |
When NG is displayed:
|
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 or upper bracket 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 |
|
|
|
7. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE AND GROUND) |
|
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
NOTICE: If the result is not as specified, check for looseness in the ground cable connection. |
|
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I59-7 (B) - Body ground |
Power switch off |
11 to 14 V |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
8. |
REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) |
(a) Replace the steering lock ECU (steering lock actuator or upper bracket assembly) with a new one and perform registration.
Click here
|
|
9. |
CHECK STEERING UNLOCK |
(a) Turn the steering wheel left and right, and then press the power 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 ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) WAS DEFECTIVE) |
| B |
|
REPLACE ID CODE BOX (IMMOBILISER CODE ECU)
|
|
10. |
CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) |
(a) Replace the steering lock ECU (steering lock actuator or upper bracket assembly) with a new one and perform registration.
HINT:
-
For replacement.
Click here
-
For registration.
Click here
(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 or upper bracket assembly) |
OK or NG |
OK: Verification result normal NG: Verification result abnormal |
When NG is displayed:
|
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 OR UPPER BRACKET ASSEMBLY) WAS DEFECTIVE) |
| NG |
|
REPLACE ID CODE BOX (IMMOBILISER CODE ECU)
|
|
11. |
CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
(a) Replace the certification ECU (smart key ECU assembly) with a new one and perform registration.
HINT:
-
For replacement.
Click here
-
For registration.
Click here
(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 |
|---|---|---|---|---|
|
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 NG is displayed:
|
Body Electrical > Smart Key > Data List
|
Tester Display |
|---|
|
S Code Check |
OK:
OK is displayed on the Techstream.
| OK |
|
END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) |
| NG |
|
REPLACE ID CODE BOX (IMMOBILISER CODE ECU)
|
|
12. |
CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) |
|
(a) Measure the voltage according to the value(s) in the table below. Standard Voltage:
|
|
| NG |
|
|
|
13. |
READ VALUE USING TECHSTREAM (STEERING UNLOCK) |
(a) Turn the power switch off.
(b) Check that the steering is locked.
(c) Connect the Techstream to the DLC3.
(d) Turn the Techstream on.
HINT:
When using the Techstream with the power 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.
(e) Enter the following menus: Body Electrical / Smart Key / Data List.
(f) 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 or upper bracket assembly) unlock confirmation status |
Unset or Set |
Unset: Unlock not confirmed Set: Unlock confirmed |
When Unset is displayed, the steering is not unlocked (the hybrid control system 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 OR UPPER BRACKET ASSEMBLY) |
|
|
14. |
READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) |
(a) Replace the certification ECU (smart key ECU assembly) with a new one and perform registration.
HINT:
-
For replacement.
Click here
-
For registration.
Click here
(b) Turn the power switch on (IG).
(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 |
|---|---|---|---|---|
|
Unlock Request Receive |
Status of steering unlock command from certification ECU (smart key ECU assembly) |
OK or NG |
OK: Certification ECU (smart key ECU assembly) sends steering unlock command (within 10 seconds of power switch turned on (ACC) or on (IG), or of hybrid control system start operation performed) NG: Certification ECU (smart key ECU assembly) does not send steering unlock command (power switch not turned on (ACC) or on (IG), and hybrid control system start operation not performed) |
|
Body Electrical > Smart Key > Data List
|
Tester Display |
|---|
|
Unlock Request Receive |
OK:
Within 10 seconds after the power switch is turned on (ACC) or on (IG) or the hybrid control system is started, the Data List item changes to "OK".
| OK |
|
END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) |
| NG |
|
REPLACE ID CODE BOX (IMMOBILISER CODE ECU)
|
|
15. |
CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) |
(a) Disconnect the I59 steering lock ECU (steering lock actuator or upper bracket assembly) connector.
(b) Disconnect the I1 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 |
|---|---|---|
|
I59-4 (SLP1) - I1-12 (SLP) |
Always |
Below 1 Ω |
|
I59-4 (SLP1) or I1-12 (SLP) - Other terminals and body ground |
Always |
10 kΩ or higher |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
16. |
READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) |
(a) Replace the steering lock ECU (steering lock actuator or upper bracket assembly) with a new one.
Click here
(b) Perform registration.
Click here
(c) Turn the power switch on (IG).
(d) Use the Data List to check if the steering lock request is functioning properly.
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: Certification ECU (smart key ECU assembly) sends steering unlock command (within 10 seconds of power switch turned on (ACC) or on (IG), or of hybrid control system start operation performed) NG: Certification ECU (smart key ECU assembly) does not send steering unlock command (power switch not turned on (ACC) or on (IG), and hybrid control system start operation not performed) |
|
Body Electrical > Smart Key > Data List
|
Tester Display |
|---|
|
Unlock Request Receive |
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".
| OK |
|
END (STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) WAS) |
| NG |
|
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
|
|
|