Description: Name: Tachometer Adapter Item Weight: 1kg Item Width: 11cm Type: Speed Sensor Car Brand: All Waterproof Level: IP67 Waterproof Cable Length: 1.6m Output Tachometer Ratio: 4 pulses\/wheel Power supply: 9~36V DC Engine Type: Diesel Gasoline Engine Model: GR01 DR01 Features Suitable for all types of diesel\/gasoline engines - Easy to install, no need to disconnect, no CANBUS\/OBD required Connection: Red: Power supply 12V DC Black: Power supply GND Yellow: Output signal (fixed 4 pulse\/wheel speed ratio) White: Switch control cable Configuration steps: 1) Connect the switch cable to enter the setting mode 2) Find the vehicle's original AC alternator, then install the DR01 on top of the alternator as below, then install it securely 3) Turn on the sensor power, the LED will remain green 4) Disconnect the switch cable, the LED will still remain green and count the pulses detected from the engine 5) Connect the switch brown cable and disconnect it again, the LED will flash 6) The sensor outputs a fixed speed RPM pulse signal with a rate of 4 pulses\/revolution, which means it will output 66.6Hz at 1000RPM. For example, if the input frequency is 100Hz @1000RPM, the sensor will convert the signal and then output 66.6Hz @1000RPM7) How to configure the tachometer? Please set your tach\/tachometer RPM ratio to 4 pulses\/rev and the meter will work normally.