Oxygen Sensor Relay: Testing and Inspection

Engine and Emission Control System Relay Inspection

Main, Fuel Pump, Starting Motor Control and Throttle Motor Control Relays

1) Disconnect negative cable from battery.
2) Remove main relay (1), fuel pump relay (2), starting motor control relay (3) and/or throttle motor control relay (4) from fuse box No.2.
3) Check that there is no continuity between terminals "C" and "D". If there is continuity, replace relay.
4) Connect battery positive (+) terminal to terminal "B" of relay. Connect battery negative (-) terminal to terminal "A" of relay. Check for continuity between terminals "C" and "D". If there is no continuity, replace relay.






HO2S Heater Relay (Integration Type Relay)

1) Disconnect negative cable at battery.
2) Remove integration relay No.2 (1) from fuse box No.2 (2).





3) Check that there is no continuity between terminals "[A]-1" and "[B]-8" of relay.
4) Connect battery positive (+) terminal to "[B]-7" terminal of relay. Connect battery negative (-) terminal to "[B]-6" terminal of relay. Check for continuity between terminal "[A]-1" and "[B]-8". If there is no continuity when relay is connected to the battery, replace integration relay No.2.