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EFI Main Relay

NOTE: On Corolla, EFI main relay may also be referred to as EFI relay or F-HTR relay. On all other models, EFI main relay may also be referred to as EFI relay.
WARNING: On Prius, read service precautions before proceeding with service procedure. See SERVICE PRECAUTIONS .
  1. Ensure ignition is off. Remove EFI main relay. See EFI MAIN RELAY LOCATION  table.
  2. To test EFI main relay continuity, using ohmmeter, check for continuity and no continuity between specified terminals on EFI main relay. See Figure and Figure .
  3. To test EFI main relay operation, apply battery voltage and ground to EFI main relay. Using ohmmeter, check for continuity between specified terminals on EFI main relay. See Figure and Figure . Replace EFI main relay if defective.
    EFI MAIN RELAY LOCATION

    Application Location
    Camry & Camry Solara In Fuse/Relay Box At Driver's Side Front Corner Of Engine Compartment
    Celica, Corolla, ECHO, Highlander & Matrix In Fuse/Relay Box At Driver's Side Front Corner Of Engine Compartment, Just In Front Of Strut Tower
    MR2 In Relay Box On Firewall At Driver's Side Front Corner Of Engine Compartment
    Prius, RAV4 & Tacoma In Fuse/Relay Box At Driver's Side Front Corner Of Engine Compartment
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