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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Access ECM behind glove box. See Figure. Using DVOM, backprobe ECM harness connector and measure voltage between ground and terminal No. 1 (Black/White wire) at ECM harness connector E5. See Figure. If voltage is not 9-14 volts, go to next step. If voltage is 9-14 volts, replace ECM.
  2. Remove EFI fuse (20-amp) from engine compartment fuse box. Inspect EFI fuse. If EFI fuse is okay, reinstall fuse. Check wiring harness and electrical connectors between EFI fuse and ECM. See WIRING DIAGRAMS article. It may be necessary to check wiring between battery and EFI fuse. For additional wiring for EFI fuse to the battery, see POWER DISTRIBUTION article in WIRING DIAGRAMS . If EFI fuse is defective, replace fuse and check for short in wiring harness and components connected to EFI fuse. See WIRING DIAGRAMS article. Repair wiring harness or electrical connectors as necessary.
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