How to Restart SIM800L module when there is no signal


I’m using an Arduino Nano with the SIM800L.
works fine.
I’m allowed to send SMS, and it sends SMS back.

My Problem:
Everything works fine, but when the modul has a bad signal (when it blinks fast), there is no chance to get a Signal again.

So i will need a Command, which resets the SIM800L modul, if it has a bad signal.


Hi Bernhard,

To check network status you can use AT+CREG? command.

And, You can use command like AT+CFUN=0 and then AT+CFUN=1 to put module in flight mode and again back to normal mode. This would simulate a network reboot.

Otherwise you can use the RESET pin present on the module to restart it.



Hello RaviPujar.

The same thing happens to me as teufber.
I am using the SIM800L for ppp in a Raspberry pi 3, but when the signal is lost for long periods the modem can not reconnect.
I do not know if the problem is at the ppp level or if the modem has frozen. The only solution is a reset?
The ppp connection attempt indicates: serial link appears to be disconnected.

Thank you.

Please create separate threads for your questions. This is someones thread,

RAVI YOU ARE A REALLY GREAT MAN , without you i never could be able to let work my sim800, thank you from a young electronic!!!

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