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.
1992 Lexus LS 400FACTORY OEM SERVICE PROCEDURE
Circuit Opening Relay
NOTE:
For more information, refer to FUEL SYSTEM CIRCUIT diagnostic chart at end of article.
- Turn ignition off. Circuit opening relay is located under right side of instrument panel, above glove box. Remove relay from vehicle. Using an ohmmeter, check for continuity between relay terminals ST and E1. See Fig 1. Check for continuity between terminals IG and FC. Ensure continuity does not exist between terminals "B" and FP. If continuity is not as specified, replace relay.
- Apply battery voltage between terminals IG and FC. Using an ohmmeter, ensure continuity is present between terminals "B" and FP.
Factory Service Tools
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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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