1990 Lexus LS 400FACTORY OEM SERVICE PROCEDURE

Circuit Protection Devices

CIRCUIT PROTECTION DEVICES LOCATION

Component Location
Circuit Breakers
A/C System Behind left side kick panel.
Defogger Behind left kick panel
Power Door Locks & Windows Behind right kick panel.
Sun Roof Behind left kick panel.
EFI Fuse (20A) In engine compartment fuse/relay block.
Fuse/Relay Block
Engine Compartment (2) On left front of engine compartment, near battery.
Passenger Compartment Under left side of dash.
Fusible Link (Main) On battery positive terminal.
Ignition Fuse (7.5A) In passenger compartment fuse/relay block.
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:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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