🚫 SIM800L Not Working? Troubleshooting Guide + Arduino Uno Interface! 🤔 | Fix Your GSM Module Now! 🔧 

hi there, sim800l's logic level is a range.we've tested and it and for us, it has worked between 3.4 and 4.4V seamlessly

@@Circuitdigest Hi, thanks for your reply. Have you measured the logic voltage of the Sim800L? The datasheet stipulates it has a 2.8v logic level and if using a 3.3v microcontroller to use a 1k and 5.6k divider network. Although higher voltages do seem to work but may cause damage in the long run

it depends on what is the voltage before the divider.. for us, the gsm module didnt start before 4V@@iantcroft

@@prathameshbarik as long as it equates to 2.8v it should be perfect 👌🏻

The voltage divider is there to protect the GSM module from 5V Arduino GPIOs. With out that level shifting the GSM module will get damaged

The SIM800 IO pins are not 5V tolerant. So use the voltage divider or a level shifter.

Set the correct baud rate. The default one is 9600. And make sure you are connecting to the correct pins. Check if the RX and TX pin swapped or not.

Hi broo your module is working or not bro

@@TahirKhan-id3dcnow it’s working

Sorry, we can't recommend any provider since we don't reside in the US. The SIM800L supports 850 / 950 / 1800 /1900 MHz bands. You may check which one of the service providers provides these bands.

Check the baud rate. make sure you have connected the rx and tx lines properly. and the power supply should also be capable of providing enough power for the gsm module.

Make sure you have provided an appropriate power supply to the GSM module. It requires higher current to operate. DOn't power it directly form Arduino, power it from external power source with at least 2A current capability.

​@@Circuitdigest brother I am also facing the same issue as above, not proceeding after "initializing", although I have checked for all the correctness needed for it to work but it is still not moving forward after initializing

hi, the SIM800L only supports 2G network. if you service provider supports and have 2G coverage in your area you can use.

​@@CircuitdigestCan I use 3g sim ? Cause 2g sims are not available in market anymore