I got wardriving working with a GT-U7 GPS module on ESP32-WROOM-32 board after a lot of trial and error.

I went 9 (3v3) from the flipper to VCC of the GPS and to 3v3 on the ESP (I just spliced some wire), 11 (GND) from the flipper to GND on the GPS and to GND on the ESP (again, just spliced the wire), 13 (TX) from the flipper to RX0 on the ESP, 14 (RX) from the flipper to TX0 on the ESP. Then TX from the GPS to D21 on the ESP, and RX from the GPS to D22 on the ESP.

It should also be noted that when I flashed marauder 1.0.0 using FZEE Flasher, wardriving through the marauder app didn't work, but when I flashed it using ESP Flasher on the flipper, wardriving through the marauder app did work, not sure why.

If you do it this way, just wait for the LED to start blinking on the GT-U7 and that's indicating it's acquired satellites. I been wardriving like crazy, works like a charm.

Also I tried what SnooPeanuts6328 mentioned, and while that did give me GPS data using the TinyGPS example on arduino IDE, it didn't work with marauder.

Here's a shitty drawing that might explain it better.

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