"E-9" in the display means the battery is almost out of power. Change the battery now. If the message reappears after the battery has been replaced, reset the meter. To reset the meter, remove the battery, press any meter button, then reinsert the battery. For further information, download the owner's booklet and refer to Chapter 7, "Changing the Battery.” Alternatively, this article gives detailed information about changing batteries in Accu-Chek products.

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