GPS is not detected on SIM808 module!

Question

I'm trying to get GPS coordinates using my SIM808 module by connecting it with Arduino. When I use this code,

#include "SIM900.h"
#include <SoftwareSerial.h>
#include "gps.h"
//To change pins for Software Serial, use the two lines in GSM.cpp.
//GSM Shield for Arduino
//www.open-electronics.org
//this code is based on the example of Arduino Labs.
//Simple sketch to start a connection as client.
GPSGSM gps;
char lon[15];
char lat[15];
char alt[15];
char time[20];
char vel[15];
char msg1[5];
char msg2[5];
char stat;
char inSerial[20];
int i = 0;
boolean started = false;
void setup() {
 //Serial connection.
 Serial.begin(9600);
 Serial.println("GSM Shield testing.");
 //Start configuration of shield with baudrate.
 //For http uses it is recommended to use 4800 or slower.
 if (gsm.begin(2400)) {
 Serial.println("\nstatus=READY");
 gsm.forceON(); //To ensure that SIM908 is not only in charge mode
 started = true;
 } else Serial.println("\nstatus=IDLE");
 if (started) {
 //GPS attach
 if (gps.attachGPS())
 Serial.println("status=GPSREADY");
 else Serial.println("status=ERROR");
 delay(20000); //Time for fixing
 stat = gps.getStat();
 if (stat == 1)
 Serial.println("NOT FIXED");
 else if (stat == 0)
 Serial.println("GPS OFF");
 else if (stat == 2)
 Serial.println("2D FIXED");
 else if (stat == 3)
 Serial.println("3D FIXED");
 delay(5000);
 //Get data from GPS
 gps.getPar(lon, lat, alt, time, vel);
 Serial.println(lon);
 Serial.println(lat);
 Serial.println(alt);
 Serial.println(time);
 Serial.println(vel);
 }
};
void loop() {
 //Read for new byte on serial hardware, and write them on NewSoftSerial.
 serialhwread();
 //Read for new byte on NewSoftSerial.
 serialswread();
};
void serialhwread() {
 i = 0;
 if (Serial.available() > 0) {
 while (Serial.available() > 0) {
 inSerial[i] = (Serial.read());
 delay(10);
 i++;
 }
 inSerial[i] = '0円';
 if (!strcmp(inSerial, "/END")) {
 Serial.println("_");
 inSerial[0] = 0x1a;
 inSerial[1] = '0円';
 gsm.SimpleWriteln(inSerial);
 }
 //Send a saved AT command using serial port.
 if (!strcmp(inSerial, "TEST")) {
 stat = gps.getStat();
 if (stat == 1)
 Serial.println("NOT FIXED");
 else if (stat == 0)
 Serial.println("GPS OFF");
 else if (stat == 2)
 Serial.println("2D FIXED");
 else if (stat == 3)
 Serial.println("3D FIXED");
 }
 //Read last message saved.
 if (!strcmp(inSerial, "MSG")) {
 Serial.println(msg1);
 } else {
 Serial.println(inSerial);
 gsm.SimpleWriteln(inSerial);
 }
 inSerial[0] = '0円';
 }
}
void serialswread() {
 gsm.SimpleRead();
}

After some time, I get this error on the Serial Monitor of Arduino:

status=ERROR

The connections are as follows:

• TX of Module = Pin 2 of Arduino
• RX of Module = Pin 3 of Arduino
• GND of Module = GND of Arduino
• 5V of Module = 5V of Arduino

The Arduino is powered by USB connected to my PC.

Here is a pic of my connections

This is SIM808 module.

SIM808 module.

• Shekhar: Yes. SMS and Call functionalities are working fine. I can send messages to my mobile phone. And what pins are you talking about? I connected GPS antenna only and nothing else.
• Shekhar: I've added images of my GSM/GPS module. Please see for yourself. Thanks.
• Shekhar: May I also ask what does pin G SDA SCL 1 2 G G 1 2 does?
• SoreDakeNoKoto: Those are just breakout pins for the SIM808's I2C peripheral. Not needed here. Do you have a USB-TTL adapter? You can try communicating with the module directly with the serial monitor, to see if it responds to the GPS commands.
• Shekhar: No. Unfortunately I don't.

Answer 1

Your problem looks similar to mine. It is possible that your module is a GNSS module and therefore doesn't work with standard AT commands, which are used in "gps.h".

First check that the GPS Module receives enough current, at least 5V -- 2A from an external source like a battery.

Then try sending AT commands in the serial monitor to check if your GPS module works properly:

#include <SoftwareSerial.h>
SoftwareSerial SIM808(2,3); //(RX-Pin,TX-Pin)
void setup() {
 Serial.begin(19200);
 SIM808.begin(19200);
}
void loop() {
 if (SIM808.available())
 Serial.write(SIM808.read());
 if (Serial.available())
 SIM808.write(Serial.read());
}

Upload this to the board an then open the serial monitor and send these commands:

AT+CGNSPWR=1

This should return OK.

After that input:

 AT+CGNSINF

This should return OK and your GPS Location in this format:

1,0,<time>,<your latitude>,<your longitude>,.......... 

If you get the following output:

1,0,19800106001337.000,,,,0.00,0.0,0,,,,,,0,0,,,,, 

It means your GPS is not set. Try to put GPS antenna outside your room, on open space.

For more information about GNSS modules go to http://www.elecrow.com/wiki/images/0/05/SIM800_Series_GNSS_Application_Note_V1.00.pdf