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Sim800l is not responding anymore after a few days of continuously working and requires restart/reset. It won’t recover by itself or respond to any commands unless a restart or power off is made. If I restart the sim800l it will work for another few days.

Same behavior on two different sim800l modules.

The module is powered by a 5v 2.5 A power supply in parallel to the raspberry pi. 115200 baud rate is set.

I have tried a DC to DC (2.5) step down buck converter to power the module with 4V 2.5A separate power supply with common GND for SIMcard, raspberry pi, and module.

I don't think poor network or Transmission burst is the problem for now. It works for 12 days in the same network conditions and then stops working for a long time.

Is someone else experiencing the same behavior? Any suggestion or information would be helpful.

Harish Chaudhary
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  • "I restart the sim800l it will work for another few days." - A quick and dirty get around around is use a real time clock module such as DS3231 to hardware trigger the 5V PSU (through the LM2596 switch on/off pin) to power off/on every 3am in the morning say. There are many reasons that Rpi crashes every couple of days - (1) software buffer/file over flows or leaking, (2) 110/220VAC main power line fluctuates (3) Rpi circuit related back EMF/EMI from home appliances such as TV set, or near by huge motor/pump starts/stops (my 28 story building has huge water tank motor and elevator, eg). – tlfong01 Jun 11 '19 at 08:35
  • I hope, I understood you correctly. My raspberry pi is working efficiently without any problem. I restart my Raspberry Pi once in a day. Since Sim800l is powered by another power supply it stays ON all the time. Although I perform an SW Reset i.e. Kill the PPP0 script and restarting it when there is no internet. It seems ineffective. 1 solution can be using GPIO with Mosfet to reset powersupply or Something else. – Harish Chaudhary Jun 11 '19 at 08:46
  • Before this, I am trying to understand what is the reason behind this problem. I will consider point (2) and (3). I think also that Point (3) can cause that in my case also. I am using some other electronic devices nearby including TV. – Harish Chaudhary Jun 11 '19 at 08:51
  • Ah, if you "restart Raspberry Pi once a day." , then my suggestion of restarting Rpi is not applicable. So let us focus on points (2) and (3). Let me think harder and come back later, perhaps tomorrow. – tlfong01 Jun 11 '19 at 09:37
  • Just for troubleshooting, you might like to make the power supply to Rpi very stable, eg, using lipo power bank just to find where the noise/spike/back EMF, EMI comes, eg. https://raspberrypi.stackexchange.com/questions/99408/pin-powered-pi-crashes-when-servos-move – tlfong01 Jun 11 '19 at 09:43
  • Yes, I am doing that already. Point (2) is also out of contest. since I am using UPS system to power the whole electronics HW. – Harish Chaudhary Jun 11 '19 at 11:24
  • It seems like a problem of SIM800X modules. Or does this only happen when the modules are connected to the RPi, and the modules work flawlessly otherwise? – Dmitry Grigoryev Jun 11 '19 at 12:01
  • In both cases, when getting power from Rpi and getting power from the external supply. I lose the Internet for days sometimes if I don't reset the card. – Harish Chaudhary Jun 12 '19 at 07:52

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