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.
2001 Lexus IS 300FACTORY OEM SERVICE PROCEDURE
Body Control Systems
- Description & Operation
- Component Locations
- Trouble Shooting
- System Tests
- Notes
- Test No. 1: Power Source Circuit
- Test No. 2: Ignition Switch Power Source Circuit
- Test No. 3: Wireless Door Lock Control Receiver Circuit
- Test No. 4 : Illumination Circuit
- Test No. 5: Hazard Switch Circuit
- Test No. 6: Taillight Relay Circuit
- Test No. 7 : Key Unlock Warning Switch Circuit
- Test No. 8 : Driver's Seat Belt Buckle Switch Circuit
- Test No. 9: Fuel Gauge Circuit
- Test No. 10: Driver's Door Courtesy Switch Circuit
- Test No. 11: Luggage Compartment Courtesy Switch Circuit
- Test No. 12: Luggage Compartment Opener Motor
- Test No. 13: Door Lock Motor Circuit
- Test No. 14: Door Unlock Detection Switch Circuit
- Test No. 15: Power Window Master Switch Circuit
- Test No. 16: Power Window Switch Circuit
- Test No. 17: Defogger Relay Circuit
- Test No. 18: Diagnostic Circuit
- Test No. 19: Wireless Door Lock Buzzer Circuit
- Test No. 20: Door Lock Control Switch Circuit
- Component Tests
- Wiring Diagrams
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.