Lowrance HDS Card Error — SD Card Fault Fix Guide

What Does This Error Mean?

'Card Error' means the chart card or recording card has a fault — corrupted, unreadable, or wrong format.
Power off, remove the card, inspect the contacts, and reinsert.
Most card errors clear after reseating.
If the card is corrupted, you may need to reformat (loses data) or replace.
Always power off before removing/inserting cards.

Affected Models

Lowrance HDS Live
Lowrance HDS Carbon
Lowrance Elite FS
Lowrance HOOK Reveal
Lowrance HDS Pro

Common Causes

Card removed while unit was on (corrupted)
Card formatted incorrectly (not FAT32)
Card slot contacts dirty
Card itself failed (end of life)
Cheap card incompatible with the chartplotter

How to Fix It

Power off the chartplotter.

Hot-removing or inserting cards is what causes most card corruption.
Always power off first.
Hold the power button until the unit shuts down completely.
Wait 10 seconds before opening the card slot.
Open the card slot.

Find the card slot on the chartplotter (usually a small door on the front or side).
Open carefully.
Note which card slot the card is in (some HDS units have two).
Inspect the card.

Pull the card out.
Look at the gold contacts on the back.
Should be clean and shiny.
If discolored or have residue, wipe gently with a soft cloth.
Don't touch the contacts with bare fingers — finger oil can cause issues.
Try the card in a computer.

Insert the card into a computer (with adapter if needed).
Does the computer recognize it?
If yes, the card is OK and the chartplotter slot may have a contact issue.
If the computer can't read it either, the card is corrupted or failed.
Replace or reformat the card.

If the card is corrupted: try formatting in a computer (FAT32 for cards under 32GB, exFAT for 32GB+).
This erases all data — back up first if possible.
If formatting fails or the card still errors, replace.
Lowrance recommends class 10 SD cards from major brands (SanDisk, Samsung).

Frequently Asked Questions

What format should the SD card be?

FAT32 for cards 32GB or smaller.
exFAT for cards larger than 32GB.
Lowrance HDS supports cards up to 64GB on most current models.
Don't use NTFS or other formats — those won't work in marine chartplotters.

Why do cheap SD cards fail in marine use?

Cheap cards have basic controllers that don't handle frequent writes well.
Marine chartplotters write constantly (sonar log, waypoints, GPS track).
The cheap card's controller eventually fails.
Spend the extra 5-10 USD for a class 10 card from a known brand — it'll outlast the chartplotter.