Not sure if you can do that. I had to buy a larger SD card for my TomTom to fit a French map on also there is a limit to the size of card you can fit. SD cards will work but some TomToms's will not work with SDHC (High Capacity) cards. The SD card must be a 2.0 GB standard card. You must download a map, an application and a voice on the card or you will get a red X. The unit will read either the SD card or the internal memory, not both.
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