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 4Runner Limited, AWDFACTORY OEM SERVICE PROCEDURE
Can Communication System
CAN COMMUNICATION SYSTEM DTC IDENTIFICATION
| DTC Code | Description |
|---|---|
| U0100 | Lost Communication with ECM / PCM "A" |
| U0164 | Lost Communication with A/C ECU |
| U1002 | Lost Communication with Gateway Module (Power Management2) |
| U1002 | Lost Communication with Gateway Module (MS Bus) |
| U1114 | Lost Communication with Main Switch Module |
Factory Service Tools
Use the Manual With the Right Hardware
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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.