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Home >> Lexus >> 1993 >> LS 400 V8-4.0L (1UZ-FE) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Back Up Power Source Circuit >> Inspection Procedure
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Inspection Procedure

INSPECTION PROCEDURE

1. Check EFI fuse.
- Remove EFI fuse from Relay Box No. 2.
- Check continuity of EFl fuse.
- If OK proceed to step 2.
- If not OK check for short in the harness and all the components connected to EFI fuse.
2. Check voltage between terminal BATT of Engine Control Module connector and body ground.
- Connect the Check Harness A.
- Measure voltage between terminal BATT of Engine Control Module connector and body ground.

Voltage: 9 - 14 volts

- If OK proceed to step 3.
- If not OK check and repair harness or connector between Engine Control Module and EFI fuse, EFI fuse and battery.
3. Are the Diagnostic Trouble Codes still in the memory when the Ignition Switch is turned OFF?
- If YES proceed to DIAGNOSIS BY SYMPTOM.
- If NO check and replace Engine Control Module.
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