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EFI Main Relay

NOTE: For more information, refer to ECU POWER SOURCE CIRCUIT diagnostic chart at end of article.
  1. EFI main relay is located in engine compartment. Using an ohmmeter, check for continuity between relay terminals No. 1 and 3. Ensure continuity is not present between terminals No. 2 and 4. If continuity is not as specified, replace relay. See Fig 1.
  2. Apply battery voltage between relay terminals No. 1 and 3. Using an ohmmeter, check for continuity between terminals No. 2 and 4. If continuity is not present, replace relay.
Fig 1: EFI Main Relay Terminal ID
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