Problem with Inkshield on Arduino Uno.

I have an InkShield connecting with an Arduino UNO. For some reason, it does not give energy to the print head. I check on the PCB board, according to Lewis's website, there should be a 20V at the pin C. But I get 0V when connecting with Aruduino. And my code is like this.

#include <InkShield.h>
#define interval 300

InkShieldA0A3 MyInkShield(2);

const int inkPin = 2;

void setup() {
pinMode(inkPin, INPUT);
Serial.begin (9600);

void loop()
if(digitalRead(inkPin) == LOW){
MyInkShield.spray_ink(0x0000); //no ink sprayed
else if(digitalRead(inkPin) == HIGH){
MyInkShield.spray_ink(0x0FFF); //every nozzle
//Serial.print ("BRO.........");
//MyInkShield.spray_ink(0x0AAA); //every other nozzle
//MyInkShield.spray_ink(0x0800); //fire one nozzle
//MyInkShield.spray_ink(0x0555); //every other nozzle

Is there anything wrong with it?