Oxygen sensor

provided:

      Resistors:      R2, R3, R4 – 1K ohm 0.25W               (brown, black, red)

                           R5 – 390R ohm 0.25W                       (orange, white, brown)

                           R6 – 10K ohm 0.25W                        (brown, black, orange)

                           R7 – 270R ohm 0.25W                       (red, violet, brown)

                           R8 – 470R ohm 0.25W                       (yellow, violet, brown)

     

       Diodes:         D2, D3, D4 – 1N4001 - 50V 3A

      Zener Diode: D1 – 9.1V 0.5W

     Capacitors:  C1, C2 – 0.1uF 50V

      LEDs:         LED1- RED, LED5- Yellow, LED6- Green

      IC:               IC - LM324 with IC socket 

     Wires:         Green, Black and Red (about 0.5-0.75 meters each) with crocodile clips

     box.

here is the diagram taken from Unitec O2 components installation guide 

PCB After installing all components

Put the cables through the whole in the box

now it's testing time:

make sure that the power supply set to independent. set one side to about 12 V and the other at 0V. connect two negative wires from power supply together. connect O2 sensor to 12V side red to "+" and black to "-". connect green wire from O2 Sensor to other side of the power supply with 0V. green LED should illuminate, which indicates that mixture is lean.

rise the voltage from 0V to about 0.4V. Yellow LED should light up and Red should turn off. this indicates that the mixture is optimal.

go higher and at around 0.7V the red LED should come up and yellow should be off. this indicates that the mixture is rich.

after successfully tested sensor can be connected to the car to check if your O2 sensor is working. also can be used in everyday driving to monitor the mixture.