LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 1997 >> GS 300 >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Controls - Basic Testing >> Fuel System >> Fuel Pump Operation >> Using Scan Tool
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Using Scan Tool

  1. Connect scan tool to Data Link Connector (DLC) No. 3. See Fig 1. Turn ignition on. DO NOT start engine.
  2. Using scan tool manufacturer's instructions, activate electric fuel pump. Listen for fuel pump operating sound and feel for pressure in fuel line near fuel filter. Turn ignition off. Remove scan tool. If fuel pump operates, check fuel pressure. See FUEL PRESSURE.
  3. If fuel pump does not operate, EFI main relay, circuit opening relay or fuel pump relay (if used) may be defective. See SYSTEM/COMPONENT TESTS article.
  4. If relays are okay, check wiring circuit and fuses. If fuel pump does not operate, check for defective fuel pump or defective fuel pump ground. See appropriate wiring diagram in WIRING DIAGRAMS article.
Fig 1: Connecting Scan Tool To Data Link Connector (DLC) No. 3 (Typical)
G97J06167Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002