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.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSTOYOTA20254RUNNER SR5, RWDREPAIR AND DIAGNOSIS (SINGLE PAGE)BODY & FRAMEDOOR LOCKSSMART KEY SYSTEM (FOR ENTRY) - DIAGNOSTICS - INTRODUCTIONSMART KEY SYSTEM (FOR ENTRY FUNCTION)PROBLEM SYMPTOMS TABLE [12/2024 - ]PROBLEM SYMPTOMS TABLE [12/2024 - ]
2025 Toyota 4Runner SR5, RWD
Problem Symptoms Table [12/2024 - ]
2025 Toyota 4Runner SR5, RWDSECTION Problem Symptoms Table [12/2024 - ]
HINT:
- If a problem occurs in certain locations or at certain times of day, check for the possibility of wave interference.
- When the electrical key transmitter sub-assembly is brought near an electrical key and tire pressure monitoring system receiver assembly (RF band), door outside handle assembly (LF band), indoor electrical key antenna (LF band) or any of the electrical key antennas (LF band), the possibility of wave interference decreases. By doing this, whether wave interference is causing the problem can be checked.
- 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.
SMART KEY SYSTEM (FOR ENTRY FUNCTION)
| Symptom | Suspected Area | Link |
|---|---|---|
| Key vehicle inside lock-in prevention function does not operate | Affected by wave interference | except Gasoline Model: Refer to Power Source Mode does not Change to ON (IG and ACC) [12/2024 - ] for Gasoline Model: Refer to Power Source Mode does not Change to ON (IG and ACC) [12/2024 - ] |
| Harness or connector | ||
| No. 1 indoor electrical key antenna assembly (front floor) | ||
| No. 2 indoor electrical key antenna assembly (rear floor) | ||
| No. 3 indoor electrical key antenna assembly (inside luggage compartment) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Transmitter battery | ||
| Power distribution box assembly | ||
| Power switch*2 | ||
| Engine switch*3 | ||
| Entry lock/unlock functions and wireless functions do not operate after new/additional key ID registration | Code registration | Refer to Entry Lock/Unlock Functions and Wireless Functions do not Operate After New/Additional Key ID Registration [12/2024 - ] |
| Main body ECU (Multiplex network body ECU) | ||
| Certification ECU (Smart key ECU assembly) | ||
| All door entry lock/unlock functions and wireless functions do not operate | Lighting system | Refer to All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate [12/2024 - ] |
| Power door lock system | ||
| Affected by wave interference | ||
| Code registration | ||
| Transmitter battery | ||
| Harness or connector | ||
| Electrical key transmitter sub-assembly | ||
| Electrical key and tire pressure monitoring system receiver assembly | ||
| Main body ECU (Multiplex network body ECU) | ||
| Certification ECU (Smart key ECU assembly) | ||
| All door entry lock/unlock functions do not operate, but wireless functions operate | Affected by wave interference | Refer to All Door Entry Lock/Unlock Functions do not Operate, but Wireless Functions Operate [12/2024 - ] |
| Electrical key transmitter sub-assembly | ||
| Certification ECU (Smart key ECU assembly) | ||
| Driver side door entry unlock function does not operate | Power door lock system | Refer to Driver Side Door Entry Unlock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| Front door outside handle assembly (for driver door) | ||
| Lighting system | ||
| Certification ECU (Smart key ECU assembly) | ||
| Front passenger side door entry unlock function does not operate | Power door lock system | Refer to Front Passenger Side Door Entry Unlock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| Front door outside handle assembly (for front passenger door) | ||
| Lighting system | ||
| Certification ECU (Smart key ECU assembly) | ||
| Driver side door entry lock and unlock functions do not operate | Power door lock system | Refer to Driver Side Door Entry Lock and Unlock Functions do not Operate [12/2024 - ] |
| Affected by wave interference | ||
| Harness or connector | ||
| Front door outside handle assembly (for driver door) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Front passenger side door entry lock and unlock functions do not operate | Power door lock system | Refer to Front Passenger Side Door Entry Lock and Unlock Functions do not Operate [12/2024 - ] |
| Affected by wave interference | ||
| Harness or connector | ||
| Front door outside handle assembly (for front passenger door) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Driver side door entry lock function does not operate | Power door lock system | Refer to Driver Side Door Entry Lock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| Front door outside handle assembly (for driver door) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Front passenger side door entry lock function does not operate | Power door lock system | Refer to Front Passenger Side Door Entry Lock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| Front door outside handle assembly (for front passenger door) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Entry interior alarm does not sound | Meter/gauge System | Refer to Entry Interior Alarm does not Sound [12/2024 - ] |
| Back door entry unlock function does not operate | Power door lock system | Refer to Back Door Entry Unlock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| License plate light assembly with back door opener switch | ||
| Back door control switch (lock switch, unlock switch) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Main body ECU (multiplex network body ECU) | ||
| Back door entry lock and unlock function does not operate | Power door lock system | Refer to Back Door Entry Lock and Unlock Functions do not Operate [12/2024 - ] |
| Affected by wave interference | ||
| Harness or connector | ||
| Back door control switch (lock switch, unlock switch) | ||
| Electrical key antenna (outside luggage compartment) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Main body ECU (multiplex network body ECU) | ||
| Back door entry lock function does not operate | Power door lock system | Refer to Back Door Entry Lock Function does not Operate [12/2024 - ] |
| Harness or connector | ||
| Back door control switch (lock switch, unlock switch) | ||
| Certification ECU (Smart key ECU assembly) | ||
| Entry unlock and unlatch functions do not operate using kick sensor*4 | Check customize setting (Kick Sensor Function) | Refer to Entry Unlock and Unlatch Functions do not Operate Using Kick Sensor [12/2024 - ] |
| Power back door system | ||
| Certification ECU (Smart key ECU assembly) | ||
| Touching unlock sensor for certain period of time does not unlock all doors | Check customize setting (Door Unlock Sensor Touch Time Adjust) | Refer to Touching Unlock Sensor for Certain Period of Time does not Unlock All Doors [12/2024 - ] |
| Power door lock system | ||
| Certification ECU (Smart key ECU assembly) | ||
| Entry lock function does not operate using close & lock function*1 | Power back door system | Refer to Entry Lock Function does not Operate Using Close & Lock Function [12/2024 - ] |
| Entry exterior alarm and answer-back buzzer do not sound*2 | Check customize setting (Wireless Buzzer Response Function) | Refer to Entry Exterior Alarm and Answer-back Buzzer do not Sound [12/2024 - ] |
| Wireless door lock control system | ||
| Power door lock system | ||
| Acoustic vehicle alerting system | ||
| Certification ECU (Smart key ECU assembly) | ||
| Entry exterior alarm and answer-back buzzer do not sound*3 | Check customize setting (Wireless Buzzer Response Function) | Refer to Entry Exterior Alarm and Answer-back Buzzer do not Sound [12/2024 - ] |
| Wireless door lock control system | ||
| Power door lock system | ||
| Harness or connector | ||
| Wireless door lock buzzer | ||
| Certification ECU (Smart key ECU assembly) | ||
| Power distribution box assembly | ||
| Main body ECU (Multiplex network body ECU) |
- *1: w/ Power Back Door System
- *2: except Gasoline Model
- *3: for Gasoline Model
- *4: w/ Hands Free Power Back Door
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra 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.