Arduino GSM Shield not responding?

i have the same problem with send sms code if any one got it please reply

hi all,

same problem uno+antenova --> stuck in "not connected"

thx nixorbot i haven't even notice that i should press the power button to launch the program. now status led is on whith but the led next to it is blinking indefinetly every 3 sec.

hope someone will post any advice.



It works for me.

I have arduino uno+antenova.

First my problem of connection was due to PIN code. I disabled it with a cellphone and then put into antenova. Second i was unable to communicate withserial port like Nixrobot. It is due to console configuration you have to set "new line" in themenu at the bottom right.

Hope it helps. ++

Hi, I have the arduino board (GSM shield V2 rev3) without antenna so i put a wifi antenna on it (same screw system). Board is Arduino Uno Rev3. IDe V1.6.4. Power supply 12V and 1 Amp. SIM card has no Pinnumber (desactivated) and work fine in a mobile phone. SIM provider is ''free'' (french provider). I do power up the shield.

Modem seems to work because example ''tools/ test modem'' works fine.

Test GPRS, Send SMS are not working... And i am totally stuck here ! I have the message ''SMS message sender'' and then nothing.

Any idea ? Thanks for giving any tip !

I had similar issues but I managed to solve it with activation of data transfer (with my provider and prepaid SIM you must activate data separately). I didn't think it matter as I wanted just SMS services... but it did ;)

Thanks for your reply ! Data is activated by default by the provider.

Finaly in my case it was link to the antenna. There must be a GSM antenna... (sounds basic, yes...). Even more important if GSM connection is poor.

I am having the same problems i have gone through many fixes for this issue but my serial console simply sits at "SMS Messages Sender".

Did the external antenna work for you rvrostaing?

Yes it changes everything even without external power supply (still recommanded). Antenna is quite cheap .

alright i am going to try that thank you so much!

Hello! I normally use a power supply of 2 Amp, see the arduino gsm shield page. I use an antenna (very important as rvrostaing said), I can initialize the gsm, receive and send sms. I don't use the Telefonica SIM but another Italian provider (Wind). I've the first version of the gsm shield. My problem is that the shield doesn't work and make the arduino uno go into tilt when there are more than ca. 15 sms on memory not read or deleted. If somebody has the same problem please answer. Bye

Hi ,

I have the same problem. I use rogers provider in Canada and connect the arduino to 12 volt , 1 Amp power supply. I try to use webclient example, GSM connect to simcard , but when try to send http commands , connection failed and the net led turn off. I try AT commands and below is the result:

79 88>AT%13%%13%%10%OK%13%%10%
88 5>AT+CGREG?%13%%13%%10%+CGREG: 0,2%13%%10%%13%%10%OK%13%%10%%13%%10%Call Ready%13%%10%
5 45>AT+CGREG?%13%%13%%10%+CGREG: 0,2%13%%10%%13%%10%OK%13%%10%%252%%240%%240%%240%%240%%240%%240%%240%%240%
69 0>AT+CGREG?%13%%13%%10%+CGREG: 0,2%13%%10%%13%%10%OK%13%%10%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%
9 41>AT+CGREG?%13%%13%%10%+CGREG: 0,2%13%%10%%13%%10%OK%13%%10%%252%
41 73>AT+CGREG?%13%%13%%10%+CGREG: 0,5%13%%10%%13%%10%OK%13%%10%%252%
73 98>AT+IFC=1,1%13%%13%%10%OK%13%%10%%240%%240%%240%%240%%240%%240%%240%%240%
106 124>%19%%17%AT+CMGF=1%13%%13%%10%OK%13%%10%
124 12>AT+CLIP=1%13%%13%%10%OK%13%%10%
12 23>ATE0%13%%13%%10%OK%13%%10%
23 29>%13%%10%OK%13%%10%
29 35>%13%%10%OK%13%%10%
35 41>%13%%10%OK%13%%10%
41 47>%13%%10%OK%13%%10%
47 53>%13%%10%OK%13%%10%
53 59>%13%%10%OK%13%%10%
59 65>%13%%10%OK%13%%10%
65 71>%13%%10%OK%13%%10%
71 115>%252%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%240%%252%%13%%10%OK%13%%10%%240%%240%%240%%240%
119 0>%13%%10%OK%13%%10%%240%%240%%240%
1 7>%13%%10%OK%13%%10%
connection failed


i am having error in pin number checking and when i comment that pin number part i cant get local IP i don’t know what is the solution i am using aircel sim and my code is

#include <GSM.h>

// PIN Number
#define PINNUMBER “0000”

// APN data
#define GPRS_APN “” // replace your GPRS APN
#define GPRS_LOGIN “” // replace with your GPRS login
#define GPRS_PASSWORD “” // replace with your GPRS password

// initialize the library instance
GPRS gprs;
GSM gsmAccess; // include a ‘true’ parameter for debug enabled
GSMServer server(80); // port 80 (http default)

// timeout
const unsigned long TIMEOUT = 10 * 1000;

void setup()
// initialize serial communications and wait for port to open:
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
// connection state
boolean notConnected = true;

// Start GSM shield
// If your SIM has PIN, pass it as a parameter of begin() in quotes
while (notConnected)
if ((gsmAccess.begin(PINNUMBER) == GSM_READY) &
notConnected = false;
Serial.println(“Not connected”);

Serial.println(“Connected to GPRS network”);

// start server

//Get IP.
IPAddress LocalIP = gprs.getIPAddress();
Serial.println(“Server IP address=”);

void loop() {

// listen for incoming clients
GSMClient client = server.available();

if (client)
while (client.connected())
if (client.available())
Serial.println(“Receiving request!”);
bool sendResponse = false;
while (char c = {
if (c == ‘\n’) sendResponse = true;

// if you’ve gotten to the end of the line (received a newline
// character)
if (sendResponse)
// send a standard http response header
client.println(“HTTP/1.1 200 OK”);
client.println(“Content-Type: text/html”);
// output the value of each analog input pin
for (int analogChannel = 0; analogChannel < 6; analogChannel++) {
client.print(“analog input “);
client.print(” is “);
//necessary delay

I fixed the error that I had.

Good job! When you solve a software problem you can only be proud of yourself! ;)

open this link

Same problem here, and the only solution that works for me was that reset routine. Thanks cabbi! :smiley:

I have the same issue, especially when the board powers up.

Looking around this forum and StackOverflow I did arrange this piece of code. It has a timeout and if the GSM module does not initialize, the software will restart.

This does NOT fix the issue itself, but does a workaround to avoid the module to get stuck. Sometime, it needs a few restarts to get the GSM Shield initialized.

void(* SoftReset) (void) = 0; // declare reset function @ address 0

void InitGSM(char* pin)
  unsigned long myTimeout = 50000; // YOUR LIMIT IN MILLISECONDS
  unsigned long timeConnect = millis();
  Serial.println("\nTrying to connect…");
  // Use async mode and requires that GSM debug mode has been set on GSM object creation
  gsmAccess.begin(pin, true, false);
  while(millis()-timeConnect < myTimeout)
     // Call this if debugging is on. Otherwise we will never reach GSM_READY…?!?
     // might not call ready too often.??? See GSM3ShieldV1AccessProvider.cpp, GSM3ShieldV1AccessProvider::begin
     // Status check
     if (gsmAccess.getStatus() == GSM_READY)
  delay(500); // Let the message printout before reset is performed!

I'm deeply investigating the why of this issue. Having the GSM debug feature on, I saw the GSM module stuck at the first AT attempt. So maybe I'll change the GSM library code to retry this first initialization step. Once this first step has passed, the other steps just run well (that's what I noticed so far)

Hope this helps,

Does the Arduino's SIM900 GSM module have the same kind of issue?


many of the problems reported here may be solved by

some short tips: 1) if you are using the MEGA board change the pinning according to "get started with GSM shield" 2) check PIN of SIM card 3) check power supply (see manual Quectel_M10) 4) switch on debug mode by // initialize the library instance GSM gsmAccess(true); // true for debugging 5) if the serial monitor only shows "AT%13%" then the autobauding failed, see the link above

Since I am avoiding autobaud and setting fixed baud rate instead I can run all examples included in the GSM library without problems.


hi dose any one fix the error with the GSM shield R3 with the " Send SMS " example the message appear "not connected " but the sim card connection available any help thanks


You have asked this question four times on here, and once on stackexchange, yet no one has answered you. Has it occurred to you that perhaps no one knows, and you may be the first person in Kurdistan to try this?

dannable: @danasorani

You have asked this question four times on here, and once on stackexchange, yet no one has answered you. Has it occurred to you that perhaps no one knows, and you may be the first person in Kurdistan to try this?

yes may be i'm the first one use that model do you have any idea ?