i think the problem is with Ultrasonic sensor. //Motor indication const int Mblue = 12; const int Mred =13; //Level LED const int Green = 10; const int Yellow = 9; const int Red = 8; unsigned long previousLevel = 0; //Passive buzzer const int passiveBuzzer = 6; //Ulatrasonic sensor const int trig = 5; const int echo = 4; long duration; float distance; unsigned long previousUltra = 0; //Relay const int Relay = 7; unsigned long previousRelay = 0; //Water sensor int sensorValue = 0; unsigned long previousWater = 0; void setup() { Serial.begin(9600); pinMode(Mblue, OUTPUT); pinMode(Mred, OUTPUT); pinMode(Green, OUTPUT); pinMode(Yellow, OUTPUT); pinMode(Red, OUTPUT); pinMode(passiveBuzzer, OUTPUT); pinMode(trig, OUTPUT); pinMode(echo, INPUT); pinMode(Relay, OUTPUT); pinMode(A0, INPUT); //Passive buzzer device on sound tone(passiveBuzzer, 1000); delay(300); noTone(passiveBuzzer); delay(100); tone(passiveBuzzer, 1500); delay(200); noTone(passiveBuzzer); } void loop() { unsigned long currentMillis = millis(); //Ultrasonic input if(currentMillis - previousUltra >= 700){ previousUltra = currentMillis; digitalWrite(trig, LOW); delayMicroseconds(2); digitalWrite(trig, HIGH); delayMicroseconds(10); digitalWrite(trig, LOW); duration = pulseIn(echo, HIGH, 30000); distance = duration * 0.017; Serial.print("Distance: "); Serial.print(distance); Serial.println("cm"); } //Water sensor input if(currentMillis - previousWater >= 1000){ previousWater = currentMillis; sensorValue = analogRead(A0); Serial.print("Level: "); Serial.println(sensorValue); } //LEVEL LED OUTPUT if(currentMillis - previousLevel >= 6000){ previousLevel = currentMillis; if(distance > 12){ digitalWrite(Red, HIGH); digitalWrite(Yellow, LOW); digitalWrite(Green, LOW); } else if(distance > 8){ digitalWrite(Yellow, HIGH); digitalWrite(Red, LOW); digitalWrite(Green, LOW); } else{ digitalWrite(Green, HIGH); digitalWrite(Red, LOW); digitalWrite(Yellow, LOW); } } //Relay and Motor indication Output if(currentMillis - previousRelay >= 1000){ previousRelay = currentMillis; if(distance > 14){ digitalWrite(Relay, HIGH); digitalWrite(Mblue, HIGH); digitalWrite(Mred, LOW); } else if(sensorValue > 250){ digitalWrite(Relay, LOW); digitalWrite(Mblue, LOW); digitalWrite(Mred, HIGH); } } } Diagram: [WhatsApp Image 2026-03-22 at 9.00.05 PM] Device: [WhatsApp Image 2026-03-22 at 9.00.02 PM] [WhatsApp Image 2026-03-22 at 9.00.01 PM] [WhatsApp Image 2026-03-22 at 9.00.00 PM] [WhatsApp Image 2026-03-22 at 8.59.59 PM] [WhatsApp Image 2026-03-22 at 8.59.58 PM] [WhatsApp Image 2026-03-22 at 8.59.57 PM]

Guys, Thank you for your help. Now, It's working well. I have only removed the 12V charger and connected the aruduino to my Pc through usb ports.

The arduino is hanging. And the passive buzzer is making noise.

Nothing jumps out that might explain your observations. Post a schematic or at least a block diagram showing how you e connected eveything, with attention to power and how it is routed to the things that need powering. a7

Always show us a good schematic of your proposed circuit. Show us good images of your ‘actual’ wiring. Give links to components.

Diagram [WhatsApp Image 2026-03-22 at 9.00.05 PM] Device: [WhatsApp Image 2026-03-22 at 9.00.02 PM] [WhatsApp Image 2026-03-22 at 9.00.01 PM] [WhatsApp Image 2026-03-22 at 9.00.00 PM] [WhatsApp Image 2026-03-22 at 8.59.59 PM] [WhatsApp Image 2026-03-22 at 8.59.58 PM] [WhatsApp Image 2026-03-22 at 8.59.57 PM]

Diagram: [WhatsApp Image 2026-03-22 at 9.00.05 PM] [WhatsApp Image 2026-03-22 at 9.00.02 PM] [WhatsApp Image 2026-03-22 at 9.00.01 PM] [WhatsApp Image 2026-03-22 at 9.00.00 PM] [WhatsApp Image 2026-03-22 at 8.59.59 PM] [WhatsApp Image 2026-03-22 at 8.59.58 PM] [WhatsApp Image 2026-03-22 at 8.59.57 PM]

Is this the same problem as your other topic ? [image] Power supply issue General Guidance I am building a automatic water supply project. But, I am facing problem with Power supply. The noise is making Arduino hang and reset. I have Ultrasonic sensor- 2x, Relay- 1x, Water level sensor - 1x, LCD display 16x2 - 1x, Active buzzer - 1x, Passive buzzer - 1x, LED(5mm) - 5x, Arduino UNO - 2x, For power supply 5V mobile charger - 3x, (500mA, 700mA, 1A) 12V charger - 2x, (5A, 1A) Capacitor - 5x, (470uF) Capacitor - 2x, (1000uF). How should i supply the power? Whare should i place the…

No, I have removed the LCD and active buzzer also i have removed one ultrasonic sensor and capacitors. I have removed the second arduino. It's completely new diagram.

Stop posting those photos, they do not help, only the diagram is helpful. How do you know there is a problem? Normally, people write stuff to the Serial Monitor. Show us what is there and post it in code tags, then tell us what you expected and how it is different from what you actually got.

Do you have a kickback diode across the pump ?

Can anybody review these code?

Projects Programming

UKHeliBob March 22, 2026, 3:07pm 9

Is this the same problem as your other topic ?

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Can anybody review these code?

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