M5 ComX GPS Module

Received a M5 ComX GPS module in the post this morning however when I unpacked it I saw signs of heat damage around the pin headers.

And also on one corner of the UBlox chip, along with corrosion marks where the chip in soldered to the board (not very clear in the picture that I cant upload as new users are only allowed 1 media link)

I was going to test the board with a USB - TTL converter however the RX/TX/GND/RST pins are marked the VCC isn’t (there is an unmarked pin next to the GND/RST connectors) but I’m very reluctant to connect up a board that could be subject to a return / replacement.

Could anyone advise on this and also if that unmarked pin is VCC as I will need to know it anyway to complete the project I am working on even if I have to return this board for replacement.

Not 100% sure but that looks like solder flux residue to me? If it is just that, isopropyl alcohol will remove it.

Had I been able to post 2 pictures you would have seen the burn mark on the top right of the U-Blox chip and the corrosion on the solder points where the chip daughter board is mounted to the PCB. I suspect from my years in electronics manufacturing that someone either flamingoed up the SMT machines solder temperature settings or put in the wrong solder reel. It happens and its sorted.
Customer services were excellent, they had a replacement on the way in under an hour that should arrive tomorrow, as always you find out how good a firm is not when things go right but when they go wrong. Great service from a company in my old hometown :)

Sounds like you have it all sorted out, that’s good to hear. Also nice that you won’t have to wait long to get the replacement.

Just posting an addendum here to pass onto anyone else working with this device, the UBlox Chip is superb in it, the board once you figure out the pin headers is excellent. However the supplied antenna is terrible.

I swapped to a High Gain 28db Active Ceramic GPS Navigation Antenna connected onto the u.FL connector available online for about £3 (which I am surprised Pimoroni don’t sell as they sell GPS & Ground Planes) and after reading this post which was contributed to by the Sales and Marketing Director of Tallysman I am using a 100mm x 100mm x 6mm square of Aluminium as a ground plane and right now indoors on test I am getting solid signals from 20+ satellites and it established a 3D lock in 20 seconds, the supplied antenna connected the same way and in the same place wouldn’t connect to any satellites despite leaving it running overnight. I also suggest if you don’t have one to buy a deburring tool (about £5 from most tool suppliers) as its the easiest way to take any sharp edges off the aluminium ground plane and also has the effect of rounding the edges as per the linked tech post above.

I apologise in advance if I have broken any forum rules but the above tech information while simple and easy has taken me a long time to research and test and is posted in the spirit of passing on useful information to other makers and users.