SD shield doesn't work with battery

hello arduino forum,

i try make gps datalogger.
evertything works fine when test arduino connected pc.
from moment plug battery arduino. sd card reader/writer doesn't work anymore.
i sure not code made because have same problem when use example cardinfo stays standard in de library.

the thing happening this:

sd card reader/writher connected arduino, arduino connected pc.
i upload sd cardinfo code , next try read whats on sd card.
this working. serial monitor must say:

initializing sd card...wiring correct , card present.

card type: sdhc

volume type fat32

volume size (bytes): 3034054656
volume size (kbytes): 2962944
volume size (mbytes): 2893


from moment plug in battery, so... arduino connected pc , battery.
its not possible anymore read sd. serial monitor this:


initializing sd card...wiring correct , card present.

card type: sdhc
could not find fat16/fat32 partition.
make sure you've formatted card

i hope can tell me whats wrong here.

greetings,

thom

what battery using?  , how?

is possible battery cannot supply sufficient current reading sd card?  trying gps lock @ same time (always current intensive)?  maybe that's knocking down voltage.  sd cards can run on 3v3 impression (particularly cheap and/or knockoff ones) become unreliable if voltage drops further.

are powering both gps , sd off arduino's 3v3?  might not able stand current.

Arduino Forum > Using Arduino > Installation & Troubleshooting > SD shield doesn't work with battery

arduino