I started recently working with a uBlox Neo 6M GPS module (data sheet http://www.u-blox.com/images/downloads/Product_Docs/NEO-6_DataSheet_%28GPS.G6-HW-09005%29.pdf). I connected it to an Arduino Uno as shown:

GPS Arduino VCC-- 3.3V RX -- D11 TX -- D10 GND-- GND

I tried this example code from TinyGps++ (of course, changing the pins and the gpsbaud to 9600, which is the gps' default).

#include <TinyGPS++.h>
#include <SoftwareSerial.h>
   This sample sketch demonstrates the normal use of a TinyGPS++ (TinyGPSPlus) object.
   It requires the use of SoftwareSerial, and assumes that you have a
   4800-baud serial GPS device hooked up on pins 4(rx) and 3(tx).
static const int RXPin = 10, TXPin = 11;
static const uint32_t GPSBaud = 9600;

// The TinyGPS++ object
TinyGPSPlus gps;

// The serial connection to the GPS device
SoftwareSerial ss(RXPin, TXPin);

void setup() {
  Serial.println(F("A simple demonstration of TinyGPS++ with an attached GPS module"));
  Serial.print(F("Testing TinyGPS++ library v. ")); Serial.println(TinyGPSPlus::libraryVersion());
  Serial.println(F("by Mikal Hart"));

void loop() {
  // This sketch displays information every time a new sentence is correctly encoded.
  while (ss.available() > 0)
    if (gps.encode(ss.read()))
  if (millis() > 5000 && gps.charsProcessed() < 10) {
    Serial.println(F("No GPS detected: check wiring."));

void displayInfo() {
  Serial.print(F("Location: ")); 
  if (gps.location.isValid()) {
    Serial.print(gps.location.lat(), 6);
    Serial.print(gps.location.lng(), 6);
  } else {

  Serial.print(F("  Date/Time: "));
  if (gps.date.isValid()) {
  } else {

  Serial.print(F(" "));
  if (gps.time.isValid()) {
    if (gps.time.hour() < 10) Serial.print(F("0"));
    if (gps.time.minute() < 10) Serial.print(F("0"));
    if (gps.time.second() < 10) Serial.print(F("0"));
    if (gps.time.centisecond() < 10) Serial.print(F("0"));
  } else {

However, I do not get the GPS LED to blink, as well as my Arduino's RX LED, so the module is not transmitting any data. This is the output from the code:

A simple demonstration of TinyGPS++ with an attached GPS module
    Testing TinyGPS++ library v. 0.92
    by Mikal Hart

    Location: INVALID  Date/Time: 0/0/2000 00:00:00.00
    Location: INVALID  Date/Time: 0/0/2000 00:00:00.00


  • Where did you get the gps from? Its possible the one you got was configured to use the uBlox binary protocol as default instead on NMEA Commented Jan 28, 2015 at 7:26
  • Another comment: I spent a while working with some of the u-blox LEA-6T gps modules, and they were REALLY intolerant of baud-rate mismatches, to the point where it wouldn't talk to my device speaking 115200 baud even through the baud rate was only ~2% off. I wound up specifically choosing a baud-rate that worked well with the local oscillator I had. I don't know if the NEO-6M modules are similar, but it could be a possibility. Commented Apr 10, 2015 at 18:51

4 Answers 4


The Neo 6M takes a bit of time to fix when first powered on. If your board is fitted with a small battery it will most probably be flat and will take an hour or two to charge up. It is there to provide charge to the EEPROM and the onboard RTC.

Also check that the leads on the battery are not shorting.

You do not get a valid data sentence out of the GPS until the RTC can sync time.

The Error message that you got from Mike Hart routine first says that there is not enough data to do a FIX and second the Date Time is not syncing.

  • 1
    I thought my GPS was faulty. Thank God I saw your answer and let my module stay ON for an hour... And guess what... It worked perfectly... The on board LED started blinking
    – Bhuvnesh
    Commented Feb 4, 2020 at 13:51

After 2 days of troubleshooting I found the solution

  1. Use 3.3 volt external supply
  2. Use voltage dividers to make 3.3 volt compatible to module
  3. go outside(open space)

That's it


Try to connect your GPS module with an FTDI cable directly to the Serial-Port of your computer (and read it with screen or any other terminal program). Once that works, proceed with the Arduino. And check what your GPS-module not blinking does mean. Usually it says there is no 'fix', which means it does not see enough satellites. The output you showed would fit into that theory. Which would mean everything is ok, except your module is not seeing the sky...

  • Thanks! There was no actual problem, it was just that I was in a close space and had no patience ;)
    – Alrro
    Commented Feb 10, 2015 at 12:18

1) Try outside or near the window. because the signal may not reach inside a house.

2)Check the connection.

3) Print the number of satellites connection to know the device is connectied by


Good luck!!!

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