What does an E-F error on my Keto-Mojo meter mean and how can I fix it?

Updated 3 weeks ago by Dorian Greenow

An E-F Error means the strip you inserted into your Ketone-Mojo meter is not getting enough blood for a reading.  Here are some tips  to help you avoid getting E-F errors and ensure you get good blood flow for easy sampling every time.

  • When you prep your lancet device, adjust the depth selector. Have your meter at hand ready to test, the check your setting of the depth selector; there are six settings for adjusting the depth of the lancet's pierce to accommodate everything from soft or thin skin to thick or calloused skin. With experience, you'll find the optimal depth for your skin. Before testing, make sure your lancet device is set to your optimal setting. 
  • Wash your hands in warm water water prior to testing. Along with helping to clean the area, it will create a little warmth, which can help with blood flow. (We also like to use an alcohol swab to clean the area before use.)
  • Rub the area before testing to encourage blood flow to the extremity.
  • Grip the finger you are going to test with your index finger and thumb of your other hand and squeeze for about 12 seconds before using the lancet. This increases hydrostatic pressure.
  • Quickly prick your with the lancet device, then wait 4 seconds. Then gently squeeze around pricked area until you have a droplet about half the size of the matchstick head.
  • Place a fresh unused strip in meter wait while it checks CH. When its ready the droplet icon flashes
  • With the strip still in the meter, bring the droplet on your finger to the tip of the strip; on contact, it will suck the blood into the strip via capillary action.
  • Let the meter countdown and give you your result. 

Following these steps, you should not receive an E-F error. With practice, you will get better at obtaining a reliable sample size. We find the glucose strips are the best to practice with because they are the most affordable.


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