Guides

Electronics troubleshooting guides for builders in India.

Practical fixes for ESP32, Arduino, power, displays, relays, GSM modules, starter kits, and the path from breadboard to PCB.

ESP32 fixes Arduino basics Sensors and I2C PCB readiness
ESP32 ESP32 WiFi Not Connecting Fix SSID, password, 2.4 GHz WiFi, router settings, DHCP, signal, power, and Arduino IDE code. ESP32 WiFi Keeps Disconnecting Fix dropouts, reconnect failures, WiFi sleep, weak signal, router settings, power dips, and blocking code. ESP32-CAM Not Working Fix camera init failed, upload wiring, FTDI issues, brownouts, WiFi stream problems, and wrong board settings. ESP32 Upload Error Fix failed to connect, timed out waiting for packet header, COM port, BOOT button, drivers, and USB cable problems. ESP32 Keeps Resetting Fix brownout, weak USB power, relay noise, boot pin problems, watchdog resets, and unstable 3.3V rails. Sensors I2C Device Not Found Fix SDA/SCL wiring, scanner code, pullup resistors, wrong addresses, voltage levels, and bus conflicts. LCD 16x2 Not Displaying Fix blank screens, black boxes, I2C address, contrast, SDA/SCL wiring, library setup, and test code. Arduino Arduino Not Detected Fix missing COM ports, USB cable problems, CH340 drivers, wrong board selection, and bootloader issues. Arduino Upload Error Fix avrdude stk500 errors, COM port issues, CH340 drivers, board settings, old bootloader, and RX/TX wiring. Relay Module Always On Fix active-low trigger logic, NO/NC wiring, floating inputs, GPIO boot states, and relay power wiring. Arduino Sensor Not Working Fix power, ground, signal pin, sensor type, library setup, breadboard problems, and raw serial readings. HC-SR04 Ultrasonic Sensor Not Working Fix no readings, zero distance, wrong values, trigger/echo wiring, ESP32 echo voltage, power, and timing. Servo Motor Jittering Arduino Fix servo shaking, buzzing, weak power, missing common ground, noisy signal, overloaded linkage, and timing issues. ESP32 Relay Troubleshooting Fix relay power, GPIO, active-low logic, COM/NO/NC wiring, and load noise. SIM800L Power Troubleshooting Fix resets, fast blink, AT command failures, and network registration issues. SIM800L No AT Response Fix UART wiring, baud rate, serial monitor line endings, common ground, power, and TX/RX level problems. ESP32 OLED Troubleshooting Fix I2C address, SDA/SCL wiring, SSD1306/SH1106, and blank displays. DHT11/DHT22 Showing NaN Fix failed temperature and humidity readings on Arduino and ESP32. Electronics Starter Kit India What students and makers should buy first, skip, and upgrade later. PCB Breadboard to PCB Checklist Move from jumper wires to reliable custom hardware. KiCad to Gerber Export Guide Prepare PCB fabrication files when your prototype is ready for a board.