How can I fix problems with the N-Tester BT or app?

Choose where the problem is and we'll guide you to the fix.

 

 

Quick checks (fix most issues)
  • Update the YaraPlus app
  • Enable Bluetooth® and location on your phone
  • Install 2 × AA (LR06) alkaline batteries in the N-Tester BT
  • Make sure your account country is supported
  • Make sure you have a stable internet connection when preparing a new N-Tester measurement

 

 

Device-related problems

 

Select the problem you're experiencing:

 

 

 

Device or parts are damaged

 

Problem:

The N-Tester BT (or parts of it) is damaged and can't perform measurements.

 

Solution:

Request a replacement from our support team. We'll send a free replacement and provide a prepaid return label for the damaged device.

 

 

Device won't turn on/LED flashes red

 

Problem:

The N-Tester BT doesn't turn on or switches off during use. A red flashing LED indicates battery issues.

 

Solution:

  1. Open the battery compartment by unscrewing the four screws with a PH1 screwdriver.
  2. Check polarity and gently bend the contacts towards the batteries.
  3. If it still won't power on, insert 2 × AA (LR06) alkaline, non-rechargeable batteries.
    • Dispose of empty batteries at a collection point.
  4. Close the compartment.
  5. Restart the measurement in YaraPlus and press the ON/OFF button only when prompted.

 

Still not turning on?

Contact our support team. We'll help you fix the problem or send a free replacement (with a prepaid return label for the damaged device).

 

 

App-related problems

 

Select the issue you're experiencing:

 

 

 

YaraPlus app crashes

 

Problem:

The YaraPlus app doesn't open or crashes during use. This is usually caused by an outdated app version or device compatibility.

 

Solution:

  1. Open your device's app store, search for YaraPlus, and install any available update.
  2. Check your device meets the requirements shown on the app page.
  3. Force close and reopen the app. If the issue persists, restart your phone.
  4. Android only: Go to Settings > Apps > YaraPlus > Storage > Clear cache.
  5. If the app still crashes, uninstall and reinstall YaraPlus.

 

Still crashing?

Contact our support team

 

 

Can't start a measurement in the YaraPlus app

 

Problem:

There is no option to start an N-Tester measurement in the YaraPlus app.

 

Solution:

  1. Start the measurement from one of these locations:
    • Activity > New activity > N-Tester measurement
    • Discover > Plan N-Tester measurement (under Atfarm)
  2. If you don't see the option, check for updates: open your device's app store, search for YaraPlus, and install any available update.
  3. If it's still missing, uninstall and reinstall YaraPlus.
  4. If it's still missing, check your account's country:
    1. Tap the profile icon on the homepage, then select Personal Details.
    2. The N-Tester BT is supported in Denmark, Estonia, Finland, Germany, Ireland, Latvia, Lithuania, Norway, Sweden and the United Kingdom. Your account must be set to a supported country.
    3. Important: You must actually be located in the country you register with. The country can't be changed later. To correct it, you must delete your account and register again. Deleting your account permanently removes all data and recommendations.

 

Still can't start?

Contact our support team

 

 

Dropdowns aren't loading/can't select crop or variety

 

Problem:

When planning a measurement, dropdown lists (for example crop, production goal or variety) stay empty or keep loading.

 

Solution:

  1. Make sure location services are enabled on your phone.
    • Even if you granted location permission to YaraPlus, the phone's location service can still be switched off.
  2. Make sure you have a stable internet connection. The app needs internet to prepare a new N-Tester measurement (internet isn't required for the measurement itself).
  3. Force close and reopen YaraPlus, then start the measurement again.
  4. If it still doesn't load, restart your phone.
  5. If the issue persists, uninstall and reinstall YaraPlus.

 

Still not loading?

Contact our support team

 

 

Phone shows Bluetooth® pairing options/asks for a PIN

 

Problem:

The phone shows Bluetooth® pairing options and/or asks for a Bluetooth® PIN.

 

Solution:

  • Don't pair in your phone's Bluetooth® settings. YaraPlus connects to the N-Tester BT automatically inside the YaraPlus app.
  • If your phone asks for a PIN, cancel it and return to YaraPlus. The app manages a temporary background connection and doesn't use a manual PIN.
  • In YaraPlus, follow the on-screen steps and allow the requested permissions when prompted.

 

Check permissions:

  • Android: Go to Settings > Apps > YaraPlus > Permissions and allow Nearby devices (Android 12+ only), Location and Precise location.
  • iOS: Go to Settings > Privacy & Security and enable Bluetooth, Location Services and Precise location for YaraPlus.

 

Still can't connect? Carry out these steps, trying to pair again after each one:

  1. Exit the pairing screen in YaraPlus, then tap Start measurements again.
  2. Toggle Bluetooth® off/on on your phone.
  3. Restart your phone.
  4. Uninstall and reinstall YaraPlus.

 

Need help?

Contact our support team

 

 

Keeps searching/blue LED flashes continuously

 

Problem:

The N-Tester BT isn't connecting, and the blue LED keeps flashing.

 

Solution:

Carry out the steps below, trying to pair again after each one. Make sure the N-Tester BT is awake: press the ON/OFF button only when the app prompts you. The blue LED should start flashing during discovery. If pairing succeeds, the blue LED will remain steady.

 

  1. Exit the pairing screen in YaraPlus, then tap Start measurements again.
  2. Toggle Bluetooth® off/on on your phone.
  3. Restart your phone.
  4. Uninstall and reinstall YaraPlus.

 

Still can't connect?

Contact our support team

 

 

Measurement and results

 

Select the problem you're experiencing:

 

 

 

Calibration fails/empty measurement won't complete

 

Problem:

During calibration (empty measurement), the app doesn't proceed or the calibration fails repeatedly.

 

Solution:

  1. Make sure the measuring head is fully closed for a few seconds during the empty measurement.
  2. Check the lens is clean and dry. Dirt or moisture can affect calibration.
  3. Make sure the N-Tester BT has enough battery. If you see a red flashing LED during start-up, replace the batteries.
  4. Switch the N-Tester BT off/on and restart the measurement flow in YaraPlus.
  5. If needed, restart your phone and try again.

 

Still failing?

Contact our support team

 

 

Many failed measurements/red LED

 

Problem:

Measurements often fail (red LED) and the counter doesn't increase, or results look inconsistent.

 

Solution:

  1. Make sure the leaf fully covers the lens in the measuring head.
  2. Measure the centre of the blade of the youngest fully developed leaf.
  3. Avoid wet, dirty, rolled or stressed leaves. If there is dew or moisture, gently wipe or brush off droplets.
  4. Check the lens and sensor are clean and dry.
  5. If you're practising, use the test disk (green glass covers the lens) to check the device is responding.

 

Still getting many failed readings?

Contact our support team

 

 

Saved measurement or recommendation is missing

 

Problem:

You tapped Save and continue later or Save and exit, but can't find your measurement or recommendation.

 

Solution:

  1. In the YaraPlus app, go to Activity > N-Tester. Your saved measurements and results appear there.
  2. Open the activity to continue the workflow or view the saved recommendation.
  3. If you have multiple farms, check you're viewing the correct farm.
  4. Check both tabs: Field assigned and Unassigned.
  5. Use the filters to narrow down by date and field.

 

Also in the web app: Completed recommendations that are assigned to a field can be found under Atfarm > Tools > Performed actions > N-Tester measurements.

 

Still missing?

Contact our support team

 

 

Contact support

 

Please contact our support team and include:

 

  • Your phone model and Android/iOS version
  • N-Tester BT serial number
  • A short description of the issue and what you've already tried
  • Screenshots or a short video, if possible

 

 

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