GPS data logger isn't starting if power supplied with battery

Hello everyone,
I made a GPS data logger with my custom design Arduino board,where it logs data like Latitude,Longitude,Time & date etc., in to a micro SD card, it's working fine when I connected it with the computer supply and watching the Serial monitor.
but when I remove all the connection with my Arduino UNO and supplied power using battery then it's not starting up at all.
what should be the problem.?

is the problem with Serial commands used in my code.? Shall I remove all of them and give a try.?
I also tried using a Diode from 3.3V to RX pin on the Atmega328p on my custom design board and it's working like a charm.

Please help.
Thank you

How are you powering your arduino on a breadboard? How are you uploading programs and connecting the serial line?

Hello @J-M-L thank you for the reply, I am using additional Arduino UNO board without atmega328P IC board, Connecting Rx of my custom board to Rx of Arduino UNO and Tx to Tx and uploading the code, meanwhile I am using 5V from the Arduino UNO and also ground lines from it.

Hi,
Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Thanks.. Tom.. :slight_smile:

Hi TOM,
Thank you very much for the reply, I made few images please check with the comment.

First picture is the block diagram where I am using to upload the code and watching the serial monitor and it’s working fine (Note : No battery is connected)

Second picture is the block diagram where I am removing the Arduino UNO and connecting the Power lines to the 3.7V to 5V step up converter, I am connecting battery to this converter.

third picture is the block diagram which shows adding a diode in between 5V to Rx or Tx of Custom design board.

Thank you

while uploading code.png

non working schmatic.png

working with diode.png

Hi,
What is the diode connected to on the arduino?
Have you got ALL gnds connected together?
Have you got a DMM?

Tom.... :slight_smile:

What is the diode connected to on the arduino?

Diode is connected from 5V to Rx of custom Arduino Mega

Have you got ALL gnds connected together?

Yes! all grounds are common

Have you got a DMM?

Yes! I have digital multi meter

Hi,

Check your 5V in both situations, at the arduino and at the GPS and SD card.

Tom.... :slight_smile:

5V is working in both the situation, I think the problem is with the Boot on reset with Atmega2560 IC.