1. Confirm that the GPS antenna and the feeder head are in good contact;
2. Check if the GPS antenna is broken or broken;
3, replace the new GPS antenna for testing
(1) If the test is OK, the GPS antenna itself may be bad;
(2) If the test is NG, it may be a problem with the motherboard. Check if the GPS connector is soldered with bad solder and check the motherboard GPS circuit.
4, confirm the replacement module.