OBD протоколы SAE J1850-PWM, SAE J1939, ISO 9141, ISO 14230, ISO 15765-4; OUTPUT SIGNALS RPM (Blue wire): This is a 12v square wave signal where the frequency increases with engine speed. The signal outputs 2 pulses per crankshaft revolution. SPEED (Green wire): This is a 12v square wave signal where the frequency increases with road speed. The output frequency is approximately 2500 pulses per kilometer (1570 pulses per mile). ENGINE RUNNING (Grey wire): This signal remains high (+12v) when the engine is stationary and is driven low (0v) when engine speed exceeds 350RPM. VEHICLE TRAVELING (Yellow wire): This signal remains high (+12v) when the car is stationary and is driven low (0v) when road speed exceeds 9 Km/h (6mph).