Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Problem Symptoms Table
HINT:
Use the table below to help determine the cause of the problem symptom. The potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
| Symptom | Suspected Area | Reference |
|---|---|---|
| Steering wheel cannot unlock (engine cannot start). | Smart access system with push-button start | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
| Main body ECU | Refer to TERMINALS OF ECU | |
| Certification ECU | Refer to TERMINALS OF ECU | |
| Power source circuit | Refer to Power Source Circuit | |
| Steering lock motor drive power circuit | Refer to Steering Lock Motor Drive Power Circuit | |
| Steering lock actuator (Steering lock ECU) | Refer to TERMINALS OF ECU | |
| Unlock position sensor signal circuit | Refer to Unlock Position Sensor Signal Circuit | |
| Refer to "Unable to Unlock steering Wheel". | Refer to Unable to Unlock Steering Wheel | |
| Steering wheel cannot unlock (after connecting Techstream to DLC3, starting engine, Data List certification ECUs item Lock/Unlock Receive data is read, and steering lock command reception records display is NO). | Smart access system with push-button start | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
| Main body ECU | Refer to TERMINALS OF ECU | |
| Certification ECU | Refer to TERMINALS OF ECU | |
| ID code box | - | |
| LIN communication line | Refer to HOW TO PROCEED WITH TROUBLESHOOTING | |
| Steering wheel cannot lock. | Smart access system with push-button start | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
| Main body ECU | Refer to TERMINALS OF ECU | |
| Certification ECU | Refer to TERMINALS OF ECU | |
| Power source circuit | Refer to Power Source Circuit | |
| Steering lock motor drive power circuit | Refer to Steering Lock Motor Drive Power Circuit | |
| Steering lock actuator (Steering lock ECU) | Refer to TERMINALS OF ECU | |
| Steering wheel cannot lock (after connecting Techstream to DLC3, starting engine, Data List certification ECUs item Lock/Unlock Receive data is read, and steering lock command reception records display is NO). | Smart access system with push-button start | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
| Main body ECU | Refer to TERMINALS OF ECU | |
| Certification ECU | Refer to TERMINALS OF ECU | |
| ID code box | - | |
| LIN communication line | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.