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.
Lexus Scan Tester
SC 400 is equipped with 2 Data Link Connectors (DLCs). Data Link Connector No. 1 (DLC1) is located in engine compartment. Data Link Connector No. 2 (DLC2) is located under left side of instrument panel. See Fig 1. Codes can be retrieved by using DLC1 or DLC2. Connect scan tester to DLC1 or DLC2. Using scan tester manufacturer's instructions, retrieve trouble codes.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.