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Hi it seems that my sim800l does not want to connect to network?
Is there something that i can check for?



If your SIM800L GSM module is not connecting to the network, there could be several reasons for this issue. Let’s troubleshoot step by step:

  1. Power Supply and Wiring:
    • Ensure that you provide sufficient power to the SIM800L module. It requires 3A current during network search.
    • Connect the GND (ground) pin before the VCC (power) pin. Disconnection in the wrong order can lead to damage.
    • Use a capacitor between the GND and VCC pins of the SIM800L, placed as close as possible to the module.
    • Keep the wires short to minimize interference.
  2. Basic Connection:
    • Connect your SIM800L to an Arduino Uno with the following connections:
      • GND → GND
      • VCC → 5V (Arduino)
      • Tx → Rx
      • RST → 3.3V
      • Rx → Tx (Use a voltage divider to drop the voltage to 2.8V, as the module works best with this voltage.)
  3. Software Configuration:
    • Use the following code snippet to initialize the SIM800L:
      // Create software serial object to communicate with SIM800L
      SoftwareSerial mySerial(10, 11); // SIM800L Tx & Rx connected to Arduino pins 11 & 10
      void setup() {
          // Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
          // Begin serial communication with SIM800L
          mySerial.println("AT"); // Handshake test
          mySerial.println("AT+CSQ"); // Signal quality test
          mySerial.println("AT+CCID"); // Read SIM information
          mySerial.println("AT+CFUN=0"); // Turn off radio
          mySerial.println("AT+CFUN=1"); // Turn on radio
          mySerial.println("AT+CREG?"); // Check network registration
      void loop() {
          // Update serial communication
      void updateSerial() {
          while (Serial.available()) {
              // Handle incoming data from SIM800L
    • Adjust the code according to your specific requirements.
  4. Network Registration:
    • Use the following AT commands to check network registration:
      • AT+COPS?: Tells you which network operator your SIM is registered with.
      • AT+CREG?: Checks the registration status (0 or 1 means registered).
      • If not registered, perform network registration using AT+CREG=1.
  5. SIM Card Considerations:
    • Ensure you use a compatible SIM card with the SIM800L.
    • Insert the SIM card correctly.
    • Enable PIN protection on your SIM card.
    • Set the correct APN for your cellular network.
  6. Signal Strength:
    • Move to a location with a strong cellular signal.

Remember to follow these steps carefully, and hopefully, your SIM800L will successfully connect to the network!