Connecting the eChook to the Car

Now that the board is sending data to the phone, it needs to have some useful data to send. All of the external connections to the board go through pluggable terminal connectors. This makes it easy to wire into the vehicle’s harness with the screw terminals, and makes the board easy to remove from the car if necessary.

There is a post with some guidance to building a Greenpower car wiring harness on the eChook forum here.

The image below shows the external interfaces to the board numbered, with details on each connection in the table.

eChook nano v1.3.1 Board Bottom View with connector pinouts

Label the connectors on the harness side to make it easier to identify them in future.

Connector Pin Out

Connector	null	Signal	Use
Power In	1	24v	Power and 24V monitoring
	2	12v	Monitoring the lower battery voltage.
	3	Ground	Main grounding point for the board.
Motor PWM	1	5V PWM Output	A PWM output. Could control the drive motor, or a fan etc.
	2	Ground reference	Ground for PWM line
RPM	1	5v Supply	5V supply for the Hall Effect Sensors
	2	Motor RPM	Pulsed 5v signal from motor hall effect sensor
	3	Wheel RPM	Pulsed 5v signal from wheel hall effect sensor
	4	Ground reference	Ground for Hall Effect Sensors
Therm	1	Temp 1 - Line to thermistor	Connection to thermistor 1. Thermistor connects between here and ground
	2	Temp 2 - Line to thermistor	Connection to thermistor 2. Thermistor connects between here and ground
	3	Ground reference	Ground connection for thermistors
Throttle	1	5v Supply	5v supply for the throttle
	2	0-5v throttle input	Analogue input for a variable throttle, or digital for a push button.
	3	Ground reference	Ground reference for throttle
Ext Buttons	1	Ground reference	Ground reference for buttons
	2	Brake Switch	Brake input for logging brake use
	3	Button 1 Active LOW digital Input	Input for 'Race Start' button needed for lap counting
	4	Button 2 Active LOW digital Input	Input for 'Switch Screen' button.
Current	1	5v Supply	5V to current sensor
	2	Current Reference Analogue input	Input from current sensor reference pin
	3	Current Sensing Analogue input	Input from Current Sense pin
	4	Ground reference	Ground reference for current sensor