NMEA Parsing Failed on Some Devices Using MC60 GNSS Module

IoT Modules GSM Module
1

Hello Quectel Support,

I am currently using the Quectel MC60 module to receive GNSS data via NMEA sentences. It works correctly on most devices. However, in some specific units, I am encountering issue “NMEA parsing failed”

I would like to understand:

  1. Possible Causes – What could be causing the NMEA parsing to fail only on certain devices?
  2. Debugging Steps – How can I identify whether the issue is due to signal quality, hardware differences, firmware configuration, or UART communication errors?
  3. Recommended Solution – What steps can I take to resolve this issue and ensure consistent GNSS data parsing across all devices?
2

Module: Quectel M60
Function Used: RIL_GPS_Read(“RMC”, rdBuff)
Problem: The function call returns iRet = -1 and errCode = -1, even though GNSS voltage is stable.

Code Snippet:
u32 iRet = RIL_GPS_Read(“RMC”, rdBuff);
if (RIL_AT_SUCCESS != iRet)
{
APP_ERROR(kLogCat_GNSS, “Read NMEA/RMC information failed. iRet=%d errCode=%d”, iRet, Ql_RIL_AT_GetErrCode());
return FALSE;
}

Log Output:
Read NMEA/RMC information failed. iRet=-1 errCode=-1

Request:
What could be causing this error despite stable GNSS power?