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Circuit Opening Relay

  1. With relay connected, ensure specified voltage is present at relay terminals. See FUEL PUMP RELAY CIRCUIT VOLTAGES table. For locations of circuit opening relay, see CIRCUIT OPENING RELAY LOCATIONS table.
    CIRCUIT OPENING RELAY LOCATIONS

    Application Location
    B2600i & 929 Behind Left Kick Panel
    Miata Under Dash, Left Of Steering Column
    MPV Mounted On ECU, Under Protective Cover On Passenger Side's Floor
    MX-6 & 626 On Fuse Block
    Protege & 323 On Passenger Side's Wall, Near ECU
    RX7 On Bracket Behind Instrument Panel
    FUEL PUMP RELAY CIRCUIT VOLTAGES

    Terminal Ignition ON Volts Ignition START Volts Idle Volts
    Fp 0 12 12
    Fc 12 0 0
    B 12 12 12
    STA 0 12 0
    E1 0 0 0
  2. If voltages are okay, remove relay from vehicle. Check relay operation using a 12-volt battery source and perform resistance tests. See Fig 1 .
Fig 1: Testing Fuel Pump Relay
G117621Courtesy of MAZDA MOTORS CORP.