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Checking Fuel Pump Operation Using Scan Tool (ES300 & RX300)

  1. Connect scan tool to data link connector No. 3. See Fig 1 and Fig 2 . Turn ignition on. DO NOT start engine.
  2. Turn scan tool on. Select ACTIVE TEST mode on scan tool. Using scan tool manufacturer's instructions, activate fuel pump. On ES300, listen for fuel pump operating sound and feel for fuel pressure in fuel inlet line at fuel filter. On RX300, listen for fuel pump operating sound and feel for fuel pressure in fuel inlet line that goes from rear of fuel rail to the fuel inlet pipe. On all models, 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 or circuit opening relay may be defective. For relay application and explanation of relay operation, see FUEL PUMP CONTROL CIRCUIT . For testing of EFI main relay or circuit opening relay, see appropriate SYSTEM & COMPONENT TESTING article.
  4. If relays are okay, check for defective fuses, fusible links or wiring. See appropriate wiring diagram in WIRING DIAGRAMS article. If fuses, fusible links and wiring are okay, check for defective fuel pump. See CHECKING FUEL PUMP OPERATION BY APPLYING BATTERY VOLTAGE TO FUEL PUMP . If fuel pump operates, check fuel pump control circuit. See FUEL DELIVERY under FUEL SYSTEM in appropriate SYSTEM & COMPONENT TESTING article.
Fig 1: Connecting Scan Tool To Data Link Connector No. 3 (ES300)
G99F50414Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Connecting Scan Tool To Data Link Connector No. 3 (RX300)
G99F50422Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002