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.
Trouble Shooting
Verify customer complaint. Perform a visual inspection, checking for open fuses, disconnected or damaged wire harnesses and components. Ensure all fluid levels are correct. Repair or replace items as necessary and recheck.
Trouble shooting of headlight system, ignition switch, key unlock warning switch, and taillight system MUST begin with the multiplex communication system. See MULTIPLEX CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If the multiplex communication system is functioning properly and no diagnostic trouble codes are stored, the body control system must be interrogated next. See BODY CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If body control system is operating properly, diagnose by symptom, see SYMPTOM INDEX table under SYSTEM TESTS .
NO RELATED
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.