Arduino based OBDII Subaru Clock Pod

Voltage level shifter to interface Arduino TTL serial communication with OBDII ISO-9141 12V serial communication.

Wire the comparator as drawn, connect to the K-line and to the arduino digital pins (see external link: http://www.clubwrx.net/forums/tutorials-diy/134423369-clock-pod-mod-subarb-select-monitor-ecu-polling-arduino.html ).