see if you can read the raw NMEA data
e.g. this works with a GPS_GY-NEO6MV2 NEO-6M on a ESP8266 12-E NodeMCU
#include <SoftwareSerial.h>
// ESP8266 SoftwareSerial
// https://circuits4you.com/2016/12/14/software-serial-esp8266/
#include <SoftwareSerial.h>
// pins Rx GPIO14 (D5) and Tx GPIO 12 (D6)
SoftwareSerial swSer(D5, D6);//14, 12);
void setup() {
Serial.begin(115200); //Initialize hardware serial with baudrate of 115200
swSer.begin(9600); //Initialize software serial with baudrate of 115200
Serial.println("\nESP8266 Software serial test started");
}
void loop() {
while (swSer.available() > 0) { //wait for data at software serial
Serial.write(swSer.read()); //Send data recived from software serial to hardware serial
}
while (Serial.available() > 0) { //wait for data at hardware serial
swSer.write(Serial.read()); //send data recived from hardware serial to software serial
}
}
serial moniotor displays
$GPGGA,153740.649,,,,,0,00,25.5,,,,,,*6B
$GPGLL,,,,,153740.649,V,M*76
$GPGSA,A,1,,,,,,,,,,,,,25.5,25.5,25.5*02
$GPGSV,3,1,10,02,20,152,,06,14,030,,11,30,066,,12,41,084,*75
$GPGSV,3,2,10,22,36,269,,25,72,083,,26,08,274,,29,58,192,*79
$GPGSV,3,3,10,31,47,297,,32,25,232,*70
$GPRMC,153740.649,V,,,,,,,150123,,,M*45
$GPVTG,,,,,,,,,M*33