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.
Communication System B
- CONNECTOR INSPECTION
Check the terminals (at the control unit and harness) on the malfunctioning LCU for disconnection, bend, and other malfunctions.
OK or NG?
- OK >> GO TO 2.
- NG >> Repair terminals and connectors.
- LCU INSPECTION
Replace the malfunctioning LCU with a known-good one, and perform the communication diagnosis. Refer to "IVMS COMMUNICATION INSPECTION ".
OK or NG?
- OK >> Replace LCU.
- NG >> Repair communication harness between the indicated LCU and BCM.
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.
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