LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 1993 >> SC 300 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Relays >> EFI Main Relay
April 5, 2026: LEMON Manuals is launched! Read the announcement.

EFI Main Relay

  1. EFI main relay is located in engine compartment. Using an ohmmeter, check for continuity between relay terminals No. 1 and 3 (ES300, LS400, SC300 and SC400), or terminals No. 1 and 2 (GS300). See Fig 1 and Fig 2. Ensure continuity is not present between terminals No. 2 and 4 (ES300, LS400, SC300 and SC400), or terminals No. 3 and 5 (GS300). If continuity is not as specified, replace relay.
  2. Apply battery voltage between relay terminals No. 1 and 3 (ES300, LS400, SC300 and SC400), or terminals No. 1 and 2 (GS300). Using an ohmmeter, check for continuity between terminals No. 2 and 4 (ES300, LS400, SC300 and SC400), or terminals No. 3 and 5 (GS300). If continuity is not present, replace relay.
Fig 1: EFI Main Relay Terminal ID (GS300)
G93H79589Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: EFI Main Relay Terminal ID (ES300, LS400, SC300 & SC400)
G93A79590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
scientia non olet · About LEMON Manuals