1996 Lexus SC 400FACTORY OEM SERVICE PROCEDURE

Defogger Relay Test

Remove relay from left side of engine compartment, in fuse/relay block No. 2. Replace relay if it does not test as follows. See Fig 1.

  • There should be no continuity between terminals No. 2 and 4.
  • Apply battery voltage across terminals No. 1 and 3. There should be continuity between terminals No. 2 and 4.
Fig 1: Identifying Rear Defogger Relay Terminals
G93D01671Courtesy of Β© TOYOTA, LICENSE AGREEMENT TMS1002
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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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