SIM800L not responding to AT command on Serial Monitor

Dear fellow Arduinions,

Im currently connecting my Arduino with my SIM800L module according to https://lastminuteengineers.com/sim800l-gsm-module-arduino-tutorial/

The SIM800L module is blinking once in 3 sec so no issues there.
However, when I want to send my first "AT" command via Serial Monitor I get no response at all...
baudrate is set to 9600 and "both NL & CR" is selected in the monitor.

The module is powered with a LiPo 3.7 v 1500 mA battery.

I already shortened 2 connections from the battery to the sim module because other forums on the internet mentioned that long cables are a common cause for not responding. (see attached foto's)

Any ideas where to possible cause may be hidden? Thank you kindly in advance.

Samuel Kusenuh

Is there a USB interfacce where you can test things? If not, then best to write up a simple interface to echo commands to the GSM module. Also make sure the baudrate is set correctly on it. Sometimes the modules may be set at a different baudrate than you expect. Make sure 9600 is the default in the datasheet.

Hi Freaklabs,

thanks for the valuable input.

I want to try your recommendation. With testing via USB interface, I would probably need as USB-to-serial device like the one in the following link right?

Or is it possible to do the testing via the arduino, similar as how I am currently (trying) to interface with the SIM800 module.

Cheers,

Sam

Hi Samkusenuh.
I'd recommend to remove the Arduino MCU from its socket and use the board as a USB/serial interface. Otherwise, pick up a USB serial interface and try to talk to the board. Once you have established that communications is possible, then try to automate it via software.