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Home >> Lexus >> 1994 >> LS 400 V8-4.0L (1UZ-FE) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Main Relay (Computer/Fuel System) >> Testing and Inspection
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Main Relay (Computer/Fuel System): Testing and Inspection

INSPECTION

1. Remove EFI Main Relay located in the engine compartment relay box.
2. Inspect relay continuity.





- Using an ohmmeter, check that there is continuity between terminals 1 and 3.
- Check that there is NO continuity between terminals 2 and 4.
- If continuity is not as specified, replace the relay.
3. Inspect relay operation.





- Apply battery voltage across terminals 1 and 3.
- Using an ohmmeter, check that there is continuity between terminals 2 and 4.
- If operation is not as specified, replace the relay.
4. Reinstall EFI Main Relay.