MKR1000 LCD problem

I’m using MKR1000 and a JHD 162A LCD Display(All from the MKR IoT bundle) and testing the LCD with the code as follow:

#include <LiquidCrystal.h> 
const int rs = 12, en = 10, d4 = 2, d5 = 3, d6 = 4, d7 = 5; 
LiquidCrystal lcd(rs, en, d4, d5, d6, d7); 
void setup() {
 analogWrite(A3, 0); // Set the brightness to its maximum value 
 lcd.begin(16, 2); 
 lcd.print("hello, world!"); 
} 
void loop() { 
 lcd.setCursor(0, 1); 
 lcd.print(millis() / 1000); 
 Blink(); // Blink without delay from example
}

This code and wiring are from PuzzleBox - Arduino Project Hub and I just adjusted en from 11 to 10, but the LCD just been lighted and with no display.
I’ve double checked my wiring and pretty sure there’s no mistake.
Any hints or ideas?

Did you try adjusting the contrast pot? What happens when you do? Black boxes?
I see that you are controlling contrast with A3? Temporarily disconnect A3 and tie the contrast to ground with a 1K resistor. Any change?

Is A3 a PWM pin on your board?

Post a photo that shows your wiring.

groundFungus:
Did you try adjusting the contrast pot? What happens when you do? Black boxes?
I see that you are controlling contrast with A3? Temporarily disconnect A3 and tie the contrast to ground with a 1K resistor. Any change?

Is A3 a PWM pin on your board?

Post a photo that shows your wiring.

Well I finally found out that I used Vcc for the LCD display but forgot that MKR1000's Vcc only provide 3.3V and is not enough for LCD. Anyway thank you for replying.
After this I really recommend to follow the steps written in this post if first to the displays: