SIM800L Troubleshooting guide (Solution when you have problem with SIM800L)

In this video, we will find a solution when we have difficulties using the SIM800L module. This SIM800Lmodule is really popular because of the price and size. But sometimes using this module is not that easy.
So this video will guide you to find the solution to your SIM800L problem.
SIM800L SMS and call tutorial :
• SIM800L with arduino T...
SIM800L AT command list to access the internet :
• HTTP/GET Request using...
You can support us and unlock premium projects code by joining our membership by clicking the link below:
/ @miliohm
Full code of this tutorial you can find at :
miliohm.com/si...
Music :
"LAKEY INSPIRED - Chill Day" is licensed under a Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
Music provided by BreakingCopyright: • [Non Copyrighted Music...

[@ultimatetutorials3627]

Oh god i have been looking for a solution for decades and finally i found it in this video. God bless you. You are the savior. Man you don't even know how grateful I am

[@miliohm]

Thanks! Don't forget to subscribe and share to your friends. So your friends will found this solution too 😉

[@icestarkiller3286]

For anyone who wants to work with the SIM800L, make sure you disable your pincode of your sim. I forgot and it took me more then 12 hours to find this problem

[@vyczn]

or use "AT+CPIN=1234" command

[@exergygroup2023]

so what was your issue? how did you know you had to disable the pincode?

[@icestarkiller3286]

@@exergygroup2023 so i wouldnt connect and it kept blinking every second. somewhere on the internet i found something that explained at commands and there i found a command for pin and it explained what the reactions. And thats how i founded out that you need to disable the pincode

[@exergygroup2023]

@@icestarkiller3286 mmm ok, thanks!, I'll check again. If you still have the link where the commands where explained I would highly appreciate it! hehe,

[@paprighosh6063]

​@@icestarkiller3286 how can i disable the pincode, pls tell

[@luismanuelvera7848]

Dude found my problem was the input voltage because of this video, thank you very very much!

[@miliohm]

Thanks!

[@javieramayav7533]

My device "was not working" and I saw various troubleshooting videos and read various forums but it was untill yours that I could finally fix it or let's say, make it work... It was basically the PSU I was using it didn't have enough mA (2A) as indicated. I was using some LIPO batteries that seems don't have enough punch. So I solved it by having the correct PSU regarding Amps. Thanks for your supprt

[@beautifulsmall]

Mine works great now Ive put the sim card in the right way round. Also a 1/4 wave ground plane antenna helps 83mm. great video. I would also recommend the AT command tester for Simcom modules GUI, for £10 its saved me hours.

[@stephencarlm.calatrava8877]

By God's grace mine worked, the set-up I had though was using two 18650 batteries in series-so total voltage was around 7.4V, and used a buck converter stepping down the voltage to around 4V and connecting the output of the buck converter, directly towards the SIM800L Mini GSM module, I made sure that the wires I used was as short as I can enable and used AWG24 solid core copper wires, I did not use any capacitors, and everything worked fined, I even used 5G capable SIM card and it worked well with no problems; hopefully those working on this had theirs working, God Bless

[@alimoaz]

Man!!!! You are so helpful. I was scratching my head for two days. But your video solved my problem I have taken help from this link and followed the exact procedure mentioned in the video. Ultimately, it was a power issue. I was giving it 3.8 volt which was not sufficient. Then I changed it to 4.1 volts and it worked. Again Thanks

[@miliohm]

Thank you!! really glad it's helpful!

[@rishababadaseshi5991]

Thankyou so much brother I have seen a lot a videos and articles about it some said 3.3v or 5v but as u said 4v i tried it and got it in first try ❤

[@paulnnamdi4098]

If u know how great this video you made it, you would really be proud. Thanks a lot. This answered problem I have been working on for weeks. This video should have more likes. I have subscribed already.

[@miliohm]

Thank you! Really appreciate it!

[@kukilp213]

Thanks a bunch for the simplified tutorial. Good work. Mine was not working due to power. I was using a ICR18650 2200mAH battery. For some reason It was unable to deliver 2Amps. Then I switched to 9V-2A auto-ID adapter. Now it is working somehow. (surprisingly no overvoltage warning). I have to check the voltage today( forgot the multimeter at office).

[@feeldulfo9387]

did it burn on 9volts?

[@shoebislamhamim2380]

thank you so much. you're a life saver. I didn't connect the gnd of my power source to the GND of arduino earlier.

[@trustmeimanengineer4081]

Thank you so much. i have allready beleave that module is broken because i did insert wrong way simcard. OMG

[@miliohm]

Thank you!

[@Sekhar_Home]

Dear, i have tried everything like putting 3.7v lithium batter or put buck converter to the SIM800L, but never it got any network. however the sim info can get from AT command and CPIN is ready/ only CREG AND CSQ shows 0.. pls help me Is there any chance that I bought an faulty SIM module?? pls tell how to check. The SIM can run fine in any 2g mobile in the home

[@hiohio2766]

Hi, I've been following your video and checked everything. The voltage is around 4.1-4.3v but the led is still blinking every 1 second. AT+CREG is 0,0 and can't send any message. Any idea why is this happening?

[@jeanmarcreyes6927]

hello same problem atm. Have you resolved this?

[@tonyyy570]

@@jeanmarcreyes6927 its a power supply issue

[@forthingsotherpeoplecantkn9645]

My SIM800L doesn't respond to AT command. The serial monitor is simply blank And the led blinks every 3 seconds wich means its connected to a network I power it trough a lm2596 buck down converter with 4v , From 12v power suply Can you help me ?

[@nameunknow9509]

i bought a sim800l module and i made it with nodemcu with 18650 lithium ion battery @ 4..2v the sim 800 module blinks 6 times and pauses a while and again 6 times and pauses please help

[@XTomsenX]

I wasted one hour cause the second antenna (for the ufl connector) doesnt work. I got zero signal quality. I changed to the small helical antenna and now it works. Is it possible that the ufl connecter have to connect somewhere at the gsm shield? Or should both PINS (ufl connector and the pin for the helical antenna) ready to use? Thank u alot!

[@LX-999]

Hello milliohm, thank you for your great videos, i have a question regarding the sim800L: i have around 20 sim cards for which i have an online platform to see any incoming and outgoing sms, so i dont need a phone for every single one of them, but to actually have the sims running, ofcourse i need power and an antenna. would it be possible to hook up loads of SIM800L together with the antenna and then have them running while i can mange all traffic over the online tool? How can i power many SIM800L at once without an arduino, only power supply

[@sant564skatex6]

Thanks!, you helped me a lot. I had 1-second constant blinking due to an unrecognized network. The solution was to buy a Simcard that supports the detected networks at AT+COPS=?

[@Sekhar_Home]

Hello how u solution ur problem?

[@KonselorSekolah1407]

The tricky part about SIM800L is the power I think

[@miliohm]

I agree :D

[@feeldulfo9387]

Do i need more than 2A for power supply when I have other hardware parts connected to same power supply with sim800L GSM module?

[@saidmohamud123]

Can I use 100ohm resistor to limit the current to the gsm?

[@DSEE-AyushAgrawal]

Hi, this was an informative video. I have found that my gsm responds "SIM WRONG" when i give command "AT+CPIN?" But its the same sim that was working earlier . Sometimes it starts working, sometimes it doesn't. Also, the my area has many 2g networks but when i give the commant AT+COPS? ..its returns 0

[@abdillahjoiya5886]

LED is blinking after 3 seconds, means sim800l has been initialized. but no messages and calls are going.

[@rudhreshvc2106]

My module blinks every 3 sec but when I run AT command it doesn't return ok and it's blank

[@vigneshreignz3860]

Bro me too same problem ❤️

[@erickay6231]

were you able to overcome this problem? if yes, then I'm facing this same problem kindly help me

[@ahmadzarara3149]

Hi, when I use AT+CSQ the module return 0.0 ..what do you think the problem Is? Every previous steps works fine,

[@rolandow2]

My module doesn't blink at all. I have a 5V 30A PSU connected to the LM2596 buck converter as you did. I was wondering if it's possible to only connect the VCC and GND pin to the SIM800L from here, just to see if the LED will start blinking. In other words: are the TX and RX pins required to make the LED blink? I want to rule out any problems with the Arduino. I think my SIM800L is defective.

[@miliohm]

Yes, the module should blinking even only vcc and ground that connected. Check the wire too. Sometimes the wire just broken

[@msandrorocha]

I faced the same problem, but in my case I use the SIM800c. The problem was solved by connecting directly the PWX with GND. I also had to change the sim card and enhance the quality of the LM2596 output by using capacitors as stated in www.bizkit.ru/en/2019/02/05/13553/.

[@izzuddinshofar]

Thanks, solved mu problem

[@rejasnambiar362]

See I am Using Sim800L module it was working absolutely fine, I have intersected the Activate sim , It was working fine no issue was their, Suddenly the gsm module ,By using AT commands it shown that Sim not inserted, As I have correctly inserted, Voltage and Current are accurate, 4.4volts and 2 Ampere, I am not getting any solution

[@GopiNath-tb7qv]

Hi, is it must to add an voltage divider in between the Rx of module and Tx of Arduino Uno?

[@badboy..312]

i need a response to this answer

[@AliRashidi97]

Hello tnx for the video I can call , but I can't send sms . Do u have anu idea why? I'm using a Lipo battery and the LED works fine.

[@shan_singh]

why not use the rx and tx pin on the arduino board instead of other pins??

[@miliohm]

The rx and tx are for serial monitor. We need both

[@shan_singh]

@@miliohm the default rx tx pins why did you make new pins as rx tx instead of using already existing pins?

[@miliohm]

@@shan_singh as I already told you, the default tx and rx pins are used for serial monitor. We need both, the serial monitor, and serial for the SIM. if you use default serial, it will mixed up between serial monitor and the at command

[@shan_singh]

@@miliohm thank you for replying. I'm still confused. What is serial for sim? you are using serial monitor and typing AT commands in it, how is it different from serial for sim?

[@technoelectronics4497]

@@shan_singh you can use rx,tx no problem. but while upload the program u ve to empty those pins and after upload the program you can connect those pins to gsm it will work. www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@vysakhak191]

AT+CCID ERROR The led is blinking once every second . what may be the issue??

[@theneelo3906]

hey brother, can i ask what is the command to register to a network?

[@82jimrock]

Hi.. practically LM2596 output has high ripples which can damage a delicate circuitry. How long have you tested this setup... for days or weeks or months?

[@miliohm]

Just for days. Maybe you can add more capacitor the decrease the ripples

[@82jimrock]

@@miliohm Thanks ...also some users adding voltage divider, at TX pin of Arduino, to step it down to 2.5V to 3.3V levels for RX pin of SIM800L board. Is that necessary?

[@technoelectronics4497]

if we use buck converter it maintain stability www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@DiegoDavicino-nk1mw]

HI , Every time on CGREG i get 2, i checked voltage is around 5 volts, any idea what happend

[@yogmayjivan9983]

Hello sir very nice video Sir can we use 4G SIM in SIM800L module ?

[@4tearff]

You can when the sim800l powerup then it searches for 2g signals, some sims they don't have this (jio).

[@brainpill7886]

If my module is not blinking, it means it's broken right?

[@aurelioroccasanta2801]

Hi, mi SIM seems to be working but most of the commands give me ERROR, AT gives me OK, AT+csq gaves me 24, AT+CFUN=1 OK, and AT+COPS works too, but for example AT+CMGF=1, AT+CIICR, AT+CPIN? and basically every other commandd i tried gives me ERROR. I use SIM800L on raspberry pi (serial connected), i pilot it from node-red. the provider of the SIM is things mobile. please help me I am really desperate.

[@Fx_Explains]

i can call the number and it rings but I don't receive sms, when pir sensor senses. is it the gsm module or pir sensor??

[@hishcodes]

AT+CREG? +CREG: 0,3 how do i fix this? please help me

[@junhaocheow1306]

HI, my gsm module sometimes is working but sometimes will show call ready or SMS ready, what it happen?

[@Techcommunity360]

Please can 4g sim work with it

[@aitchjayem2294]

hi everybody, i'm dealing with a big issue, i bought the 800l module and because i was busy i just wanted to test if it works, so i connected it directly to the Arduino Uno like this : tx-->rx rx-->tx 5v-->vcc gnd-->gnd without putting the sim card the gsm module's LED started blinking after 3 days i did the same but this time with the sim card the gsm module doesn't work at all, the LED doesn't even turn on with/without sim card i checked if the LED is working using an external circuit and it worked i don't even know where the problem is or even if it has been corrupted

[@summerfun6114]

Great! can it be used in hardwareSerial? Thanks.

[@miliohm]

Sure

[@luxolombono7635]

hello, my Sim800L module returns +CSQ:0,0 when I insert sim card but when I remove it gives me +CSQ:24,0. I am using 3.7v Li-Po Battery, what could be the problem?

[@feriandrisaputro3276]

How about if AT+COIN?=Error and led is still blinking every second

[@frymazhafran9084]

hi, thx for the video it helps me a lot. but i have a question, when i follow your way to troubleshoot i didn't have any trouble, except when i check my sim card registration using AT+CREG? it always show 0,0 or 0,3. and then i had check my power supply and set it right as the datasheet but the indicator still blinking every 1 sec. how do you think to solve it? thx once again, sorry for my bad english

[@miliohm]

Try increase the voltage. 5V is still tolerable. Then restart the SIM by unplug the power. If still doesn't work try AT+CREG=1. By the way what happened when you type AT+COPS?

[@frymazhafran9084]

@@miliohm okay I will try it, when I type AT+COPS? it shows the list of network too same like in your video

[@lf-m516]

@@miliohm Hi bro, when I check my sim card registration using AT+CREG? it always show 0,2 or 0,4, and I used 4.3 Vdc. can you help me ? please

[@frymazhafran9084]

@@miliohm I type AT+CREG=1 and then when I tried check it with AT+CREG? It come +CREG: 1,3. I Think it is still not correct, i was increase the voltage too to 5v btw

[@miliohm]

@@frymazhafran9084 did you already check the sim with your phone? and did you already try with another operator? Im not sure what's wrong

[@TusharKumar-iu4nt]

Can you tell the model of the transformer?

[@azaholmes6432]

Can I connect my step down power supply module to the 5V of the arduino? is this better in this way?

[@miliohm]

Sure

[@MakerVerse]

Looks like it only works in 2G network so thit is probably why it doesn't work for me, and my COPS shows only one network in witch i cant connect into. I'm using a separate power supply two batteries battery 18650 (7v+) with a dc dc step down to 4.0v

[@scroogemcduckenjoyer]

Mantap, susah banget ni modul settingnya

[@rafaeladela8829]

my SIM800L module blinks every 3 seconds but can't communicate with it via serial. the serial monitor doesn't show my AT command inputs when entered and the response, just blank. Does that mean I have something wrong with the connection/wires? (using your code) if i use a sketch where it will type the at commands for me, the module stops blinking when I open serial monitor Note: I have set the serial monitor settings to Both NL & CR

[@clementszumny1288]

hello, i have the same problem, did you find a solution?

[@rafaeladela8829]

@@clementszumny1288 still finding solutions. Some say that sim800l requires 38400 baud rate. I did try it but i still got no response on serial monitor. Also it is noted that sim800l cant tolerate 5v signal so you might want to put a voltage divider to have an 3v output from arduino tx to sim800l rx.

[@clementszumny1288]

@@rafaeladela8829 ok I just tried with 38400 baud rate but I also have nothing. And did you try to divide the output voltage ?

[@clementszumny1288]

@@rafaeladela8829 but that's strange because when i power the sim800l the led is blinking every second, means that it try to connect to the network, then i send the command : "AT+CPIN=1234" for the pin code and the then the led is blinking every 3 seconds, so i guess that means my arduino is able communicate with the sim800l but the module doesn't answer to the arduino, i really don't understand why...

[@rafaeladela8829]

@@clementszumny1288 yes as i am using an arduino uno which outputs 5v on its digital pins. I had to add voltage divider to get 3.3v to the rx pin of sim800l. If youre microcontroller outputs 3.3v, then there is no need to add voltage divider.

[@adityagoyani5716]

hellow sir i need your help. i get twice blinking in 35 second .....means simm800l is binks twice and does responce for 35 second . what should i do?

[@riazmuhammad578]

sir the led of our GSM 800L blinks every 1 second what is the solution How we can connect it to the network operator?

[@radosawprzezdziek4610]

Please tell me how ending typing sms message text in serial monitor. I can't confirm my message for send. I tryed ctrl + z , ctrl + x, ctrl + backspace, ctrl + shift + x... etc. Ofcourse i set up terminal like you For NL and CR .

[@miliohm]

it's on the link, on the end of article

[@aminvaali]

Great video. thank you

[@miliohm]

Thank you!

[@braveheart9275]

Hello ... please help. when I send at+cmgf=? , the module return error. what ca I do ?

[@pateldhruv4657]

My module can receive messages and also do call .but module can't send messages So what to do?

[@pateldhruv4657]

If I connected rx to rx and tx to tx ,so may be it's happened?

[@abdillahjoiya5886]

what is the assembly of Rx and Tx for arduino mega

[@thirugnanasambanthamk9273]

Can i provide the laptop as a power supply

[@ultimatetutorials3627]

What can i do if i want to show the received sms on an I2C display

[@jihensouaied8659]

when i tape AT+CREG? the module send +CREG: 0,2 ,what does it mean?

[@miliohm]

it's not registered. but trying to register to network. Try increase the voltage for supply. Or try use 5v from arduino. sometime it just works.

[@jihensouaied8659]

thanks a lot!

[@ahmednabeelhijejoo4013]

My SIM800L not working upon being turned off and on after sketch is loaded

[@mohammadatiah735]

Hello brother, I want to ask you about the sim800l electronic part. I am doing in a project and there is no broadcast. What should I put a SIM and it is in my city 2G or 3G? Thank you, brother. I hope you help as soon as possible

[@shamilazim7173]

2g

[@user-nh9uw4ks6i]

I had the problem of not receiving the caller's number only the word RANG

[@calmrelaxed7626]

sir it doesnt reply to at commands..I tried everything.What to do

[@bikicviki]

Where can I find firmware 1418B04SIM800L24 for SIM800L?

[@curiosity_gg]

Bang, kalo sim800l reset sendiri (lampu kedip² setiap detik lalu diam sekitar 3 detik lalu kedip² lagi) itu kenapa ya? Saya pakai lm2596 stepdown.

[@raoufmhadhebi9395]

Thanks

[@horyshet9891]

Hi i have a question,The sim800l that I'm working onwas doing fine, it is registered on the network, can send message and can also receive messages, but, when I try to run a program that sends a reply after receiving a specific sms which was "location", It cannot send a message back, though It can receive the text message well, It somehow was not able to send a reply back. The sim800l is powered by arduino uno , still did not work, also tried using a two li-oon 18650 3.7v 2200mah as a power source and it still did not work. Any possibile solution on this one?

[@erickay6231]

were you able to overcome this problem. I'm currently facing this same problem and if yes, how did you do it. pls help I have less than a month to present my project

[@horyshet9891]

@@erickay6231 yeah, seems like the network provider of my sim banned the sending of URL, so Instead of sending google map links, I just sent raw coordinates

[@horyshet9891]

​@@erickay6231turns out my SIM network provider blocked the sending of URL so i sent raw coordinates instead of google map links

[@asshahidm]

Which sim is ised in this

[@AmanPatel-rv2it]

Will the jio sim work on it

[@anjaligupta7843]

GSM SIM800L can what is L?

[@gabrielintriago1458]

Hello. What can I do if responses "2" to the AT+CREG??

[@meenakumari8112]

"3" Rply 😭😭😭😭

[@miruee]

Bang, saya nyoba CPIN balesannya Error, AT+COPS=1,2,"51010" juga error, itu knp ya. Error doang gak ada keterangan apa apa lagi

[@mehdi7939]

All is fine for me, but i have an issue when sending the message , the prefix of my country is "+216" doesn't work, have you any idea ?

[@karimkalboussi4703]

ya bro bellehi kifech 5addamtha ? merci d'avance

[@tkrox8379]

10:03 Perfect blur btw

[@jelleseelig8681]

My sim800l is blinking once a seconds it’s running with a Buck converter on 4.1V can you help me please I’m trying it since one week

[@miliohm]

Try increase the voltage. 5v max. Sometime it just works using 5V. How much ampere is your power supply at?

[@poojaelectronics9382]

WHEN I AM USING AT+CMGF=1 COMMAND IT GIVE ME ERROR AND I COULD NOT SEND MESSAGE. PLEASE SOLVE MY PROBLEM

[@harshshukla8339]

In ide msg sent is done but i not recived sms what is problems

[@meenakumari8112]

AT+CREG? Resposed "3" Ples help me

[@melvinthung1734]

Bang, knp ya sim 800l saya tdk mengirimkan sms? Padahal status pada serial monitor udah finish mengirim sms, tpi gk ada sms masuk ke no tujuan yg sdh diseting Apakah itu imei diblok kah? Atau gmna bang? Mohon solusinya bang, soalnya ini utk tgs akhir saya bang🙏

[@yawarsaeed6499]

Awesome !!!

[@KJC432]

Is there's someone who have the same problem with me because the led light of my sim800l gsm module is not blinking but it stay on.

[@jerome2617]

What you use for the step down?

[@miliohm]

To decrease the voltage, it should not more than 4.2V

[@technoelectronics4497]

you better to use the buck converter www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@rendijakasusanto1351]

gan mau izin tanya, sim800l ku udah bisa dapet jaringan. cuma kalau dia dipake http get/post pake library langsung reconnect setelah satu kali bisa, kira kira kenapa yaa

[@bartoosterkerk682]

What if simcard has a pincode?

[@bartoosterkerk682]

Most cards have them

[@alexandreleite4156]

hi can you pls explain how to send the CRTL+Z to end the text message?

[@miliohm]

you can use this char -> 

[@technoelectronics4497]

Serial.write(0x1a); www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@Ajaypatil-ev4qh]

MY LED IS BLINKING AFTER 3 SEC BUT WHEN I TRIED FOR SERIAL COMMUNICATION I AM GETTING REPLY FOR "AT" AS "AT?" I TRIED CHANGING EVERY BAUD REATE BUT STILL I AM NOT GETTING "OK" FOR OUTPUT

[@technoelectronics4497]

once you can check your baudd rate, are you mention in the program are not www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@numanerdogan2119]

AT+CREG? +CREG: 0,0 WHY?

[@numanerdogan2119]

and always 1 sec blink.

[@exergygroup2023]

@@numanerdogan2119 did you solve it? please help me i'm having the same issue

[@aulyafithriahanifah2650]

hi sir, why i always get ERROR when i give command "AT+SAPBR=1,1"?

[@miliohm]

Coba AT+CIICR

[@aulyafithriahanifah2650]

@@miliohm terima kasih bang

[@aulyafithriahanifah2650]

@@miliohm bang klo stlh dikasih command AT+CIICR munculnya +PDP: DEACT knp ya?

[@zhuk462]

TX pin is 3.1V max! you may burn the module!

[@pateldhruv4657]

My Gsm module light blink 7 time and after that it not blink in 3 sec after that repeat same for all the Plz give me suggestions what I do ?

[@miliohm]

I think that's caused by power. When it is trying to register. The power is not enough. What power supply did you use?

[@pateldhruv4657]

@@miliohm ardino board use to power Gsm module

[@miliohm]

@@pateldhruv4657it's the 5V? Try another power supply with more power

[@pateldhruv4657]

@@miliohm it 5 volt but in series use diode so output voltage around 4.3 V

[@pateldhruv4657]

@@miliohm okay

[@vishalanlokanathan6156]

My gsm 800l doesn't seem to power on with 3.7V lipo battery why?

[@technoelectronics4497]

use minimum 4.5v with 1 amp ratings it will work better www.technoelectronics44.com/2020/11/gsm-sim800l.html

[@erickay6231]

dude were you able to overcome the problem. help me because I'm encountering the same problem

[@miguelguty399]

hi, your sim es 4g?

[@miliohm]

Yes

[@calmrelaxed7626]

I followed everything you told but it doesnt accept AT commands

[@miliohm]

Is the SIM LED already light up? And make sure the tx and rx pins are right.

[@calmrelaxed7626]

@@miliohm yes its blinking once for 3 seconds

[@erwintrianandaerwin6265]

Hello sir, I have a problem in the sim800l module version 2, while looking for the signal to restart continuously... How to solve the problem?

[@miliohm]

What kind of power supply did you use? Sometimes it caused by insufficient power. And try give it an capacitor.

[@erwintrianandaerwin6265]

@@miliohm I use 5volt power from arduino, If given a capasitor of what size? And given to which pin?

[@miliohm]

Try use power supply with more current like 2amp minimum. Use 100uF capactor between vcc and gnd

[@erwintrianandaerwin6265]

@@miliohmok sir, Thanks for the response... I'll try it...

[@BlazeArc5943]

Hi there, I have the problem that when I enter AT it replies "⸮⸮⸮" these inverted question marks. I don't know whats the problem kindly guide

[@BlazeArc5943]

and when I make a call to the sim in GSM module serial monitor shows same response

[@miliohm]

Try change the baudrate. For example 115200

[@widiyantonugroho9012]

video yang bermanfaat bang. mantap. tapi saya mau tanya, kenapa sim 800L saya ga bisa send SMS ya? AT command oke semua, saya masukkan perintah SMS yang terjadi justru modul melakukan call sesaat, ketika saya masukkan perintah telepon 15 detik, yang terjadi juga sama.. modul melakukan call sesaat kurang dari 2 detik. Padahal power supply & AT command normal semua. Mohon bantuan bang..

[@miliohm]

pakenya AT+ apa mas?