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.
1997 Lexus SC 300 AutomaticFACTORY OEM SERVICE PROCEDURE
Circuit Testing: Notes
WARNING: This page is about a different car, the 1997 Lexus SC 400. However, it is still accessible from the selected car via links, so may be relevant.
CIRCUIT TESTING
| Test | Description |
|---|---|
| TEST 1 | STOPLIGHT SWITCH CIRCUIT |
| TEST 2 | IDLE SWITCH CIRCUIT |
| TEST 3 | ELECTRONIC-CONTROLLED A/T COMMUNICATION CIRCUIT |
| TEST 4 | ELECTRONIC FUEL INJECTION COMMUNICATION CIRCUIT |
| TEST 5 | PARKING BRAKE SWITCH CIRCUIT |
| TEST 6 | NEUTRAL START SWITCH CIRCUIT |
| TEST 8 | ECU POWER SOURCE CIRCUIT |
| TEST 9 | BACK-UP POWER SOURCE CIRCUIT |
| TEST 10 | CRUISE CONTROL MAIN SWITCH CIRCUIT |
| TEST 11 | DIAGNOSTIC CONNECTOR CIRCUIT |
| TEST 12 | INDICATOR LIGHT CIRCUIT |
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.