Arduino SoftwareSerial - can't get data from NEO 6M-GPS module
RX of the Arduino (pin 4, according to the SoftwareSerial statement) goes to the TX of the GPS.  Arduino pin 3 (ss TX) goes to the GPS RX.

And you should use pins 8 &amp; 9 instead.  That would let you use AltSoftSerial, the best choice when you can't use HardwareSerial (i.e., Serial).

If you can't use pins 8 &amp; 9, then NeoSWSerial is a better choice than SoftwareSerial.

And while I'm promoting NeoSWSerial, I'll mention a library I wrote, NeoGPS...  It's faster and smaller than all other GPS libraries, and very configurable.  It also has several diagnostic programs and a Troubleshooting section in the docs.