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.
2012 Toyota Prius TwoFACTORY OEM SERVICE PROCEDURE
Problem Symptoms Table
WARNING: This page is about a different variant/trim than selected.
HINT:
- Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, 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.
- Inspect the fuses and relays related to this system before inspecting the suspected areas below.
ENGINE IMMOBILISER SYSTEM
| Symptom | Suspected Area | See |
|---|---|---|
| Hybrid control system does not start. | Key | Refer to DATA LIST / ACTIVE TEST |
| Smart key system (for start function) | Refer to HOW TO PROCEED WITH TROUBLESHOOTING | |
| Hybrid control system | Refer to HOW TO PROCEED WITH TROUBLESHOOTING | |
| Security indicator light does not blink. | Certification ECU (smart key ECU assembly) | Refer to Security Indicator Light Does not Blink |
| Wire harness or connector | - | |
| No. 3 meter circuit plate | - |
Factory Service Tools
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.
Comes to youSame-day available12-month warranty
Get a Free QuoteNo obligation. See pricing before you book.