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Using Scan Tester

  1. Remove instrument panel fuse box cover. Connect scan tester to Data Link Connector (DLC) No. 3. See Fig 1. Turn ignition on. DO NOT start engine.
  2. Using scan tester 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 tester. 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 TESTING 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 Tester To Data Link Connector (DLC) No. 3
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