Water entering the Electronics Box can happen after impacts, board flex or a compromised seal. Learn what to do if fresh or salt water enters your unit, how to protect your electricals, and what to check if you’re experiencing repeated water ingress.

<h1 style="line-height: 2; text-align: left;" id="isPasted">This article explains how to prevent water ingress, what to do if water enters your Electronics Box, and how to correctly use dielectric grease to protect your electrical connectors from corrosion.</h1>Water Entered My Electronics BoxIf water enters the battery compartment, don&apos;t panic.The Gen2 and Gen2.5 electronics are fully sealed.The only components that require attention are the electrical connectors and the battery.<h2 style="line-height: 2;" id="if-salt-water-entered-the-unit">If Salt Water Entered the Unit</h2><ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Remove the battery.</li><li style="font-size: 14px; line-height: 2;">Drain all water from the unit.</li><li style="font-size: 14px; line-height: 2;">Rinse the battery compartment thoroughly with fresh water to remove salt residue.</li><li style="font-size: 14px; line-height: 2;">Allow the unit to drain and dry.</li><li style="font-size: 14px; line-height: 2;">Dry the battery connector.</li><li style="font-size: 14px; line-height: 2;">If the battery terminal is free of corrosion, reapply dielectric grease to the battery terminals.</li><li style="font-size: 14px; line-height: 2;">Reinstall the battery once dry.</li></ol>Removing salt is the most important step, as salt accelerates corrosion.Important: If there is damage to the battery heat shrink or outer shell - do not use the battery or attempt to charge it. Reach out to <a href="mailto:support@foildrive.com">support@foildrive.com</a> with clear, detailed photos so we can assess the battery.&#xA0;<h2 id="if-fresh-water-entered-the-unit">If Fresh Water Entered the Unit</h2>Fresh water is much less of a concern.Simply:<ul data-spread="false"><li style="font-size: 14px; line-height: 2;">Drain the water.</li><li style="font-size: 14px; line-height: 2;">Dry the compartment.</li><li style="font-size: 14px; line-height: 2;">Reapply dielectric grease to the connectors.</li><li style="font-size: 14px; line-height: 2;">Reinstall the battery.</li></ul><h1 style="line-height: 2; text-align: center;" id="isPasted">Preventing Water Ingress</h1>If you&apos;re regularly finding water inside the unit, there are several things to check:<ul data-spread="false"><li style="font-size: 14px; line-height: 2;">Ensure the O-ring is correctly installed.</li><li style="font-size: 14px; line-height: 2;">Check that the O-ring is clean and free from sand, dirt or debris.</li><li style="font-size: 14px; line-height: 2;">Check that the battery latches are correctly fitted and in good condition.</li><li style="font-size: 14px; line-height: 2;">Check for damage to the unit or sealing surfaces.</li><li style="font-size: 14px; line-height: 2;">Check that your board is sufficiently rigid for the Foil Drive installation.</li></ul><h3 style="line-height: 2; text-align: center;" id="board-flex">Board Flex</h3>Some boards may flex significantly under load.If the board is too flexible, the movement of the board can place additional forces on the more rigid Foil Drive unit. During impacts or landings, this movement can momentarily affect the seal and allow water to enter the battery compartment.If you&apos;re experiencing repeated water ingress, check the rigidity and compatibility of your board and Foil Drive setup.Water Ingress with AXIS Pocket TrenchIf you regularly find water inside the Electronics Box when using an AXIS Pocket Trench, first check that:<ul><li id="isPasted" style="font-size: 14px; line-height: 2;">There is no damage to the Electronics Box or sealing surfaces.</li><li id="isPasted" style="font-size: 14px; line-height: 2;">The AXIS mounting hardware and sliders are installed correctly.</li><li style="font-size: 14px; line-height: 2;">The Pocket Trench is free from sand, gravel and other debris that could prevent the Foil Drive from sitting correctly.</li><li style="font-size: 14px; line-height: 2;">The board and Foil Drive are being installed in accordance with the&#xA0;<a href="https://help.foildrive.com/en-US/installing-your-foil-drive-on-an-axis-pocket-trench-board-7428247" target="_blank" rel="noopener noreferrer">AXIS Pocket Trench installation instructions</a><a href="https://help.foildrive.com/en-US/installing-your-foil-drive-on-an-axis-pocket-trench-board-7428247" target="_blank" rel="noopener noreferrer">.</a></li></ul><h2 id="isPasted" style="line-height: 2; text-align: center;">Using Dielectric Grease</h2>Dielectric grease helps protect electrical connectors from moisture and corrosion.Apply a small amount of Foil Drive dielectric grease around the plug on the battery.Do not apply excessive amounts of grease. Too much grease can interfere with the electrical connection and affect power delivery.<h1 style="line-height: 2; text-align: center;" id="need-more-help">Need More Help?</h1>If you&apos;ve worked through these troubleshooting steps and are still experiencing battery issues, please contact the Foil Drive Support Team.<h1 id="isPasted" style="text-align: center; line-height: 2;"> </h1>

Gen2 & Gen2.5 – Water Ingress Troubleshooting

This guide explains how to safely test the Electronics Box with and without the battery installed, and what to check if water is found inside.

If you suspect your Assist or Assist PLUS Electronics Box is allowing water inside, a&#xA0;fresh-water dunk test can help determine whether the box is leaking and, in some cases, identify where the water is entering.This is a practical troubleshooting test that can be used alongside a&#xA0;visual inspection of the Electronics Box, including checking the lid, latches, seals, hinges and other components for damage.Important: Always perform the initial dunk test without the battery installed. The battery should only be installed for the second stage of the test if required.For instructional video, see:&#xA0;<a href="https://youtu.be/ygAwSiOlK8s" target="_blank" rel="noopener noreferrer">Fresh Water Dunk Test Guide</a><h2 id="isPasted" style="line-height: 2; text-align: center;">What Is a Fresh-Water Dunk Test?</h2>The dunk test involves placing the closed Electronics Box into a container of&#xA0;fresh water and applying gentle pressure to different areas of the box.The test can help identify:<ul data-spread="false"><li style="font-size: 14px; line-height: 2;">Whether the Electronics Box is allowing water inside.</li><li style="font-size: 14px; line-height: 2;">Whether air bubbles escape from a potential leak point.</li><li style="font-size: 14px; line-height: 2;">Whether movement or pressure on the box causes water to enter.</li><li style="font-size: 14px; line-height: 2;">Whether the cable or lid area may be contributing to the leak.</li></ul>Do not perform this test in salt water. Use clean, fresh water only.<h1 id="isPasted" style="line-height: 2;">Step 1 &#x2013; Test Without the Battery</h1>Before starting:<ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Remove the battery from the Electronics Box.</li><li style="font-size: 14px; line-height: 2;">Perform your normal visual inspection.</li><li style="font-size: 14px; line-height: 2;">Check the&#xA0;lid, latches, seals, hinges and cable entry points for obvious damage or issues.</li><li style="font-size: 14px; line-height: 2;">Close the Electronics Box normally and make sure the lid is properly secured.</li></ol><h3 style="line-height: 2;" id="dunk-the-electronics-box">Dunk the Electronics Box</h3><ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Place the closed Electronics Box into a container of&#xA0;fresh water.</li><li style="font-size: 14px; line-height: 2;">Give the box a gentle shake while it is underwater.</li></ol>This helps remove any air bubbles trapped against the outside of the box. Trapped air bubbles can otherwise be mistaken for bubbles escaping from a leak.<ol data-spread="false" start="3"><li style="font-size: 14px; line-height: 2;">Gradually submerge the box deeper into the water.</li></ol>The deeper the box is submerged, the greater the water pressure acting on the Electronics Box.<ol data-spread="false" start="4" id="isPasted"><li style="font-size: 14px; line-height: 2;">Look closely at the box for any bubbles escaping from a particular location.</li><li style="font-size: 14px; line-height: 2;">Gently move or wiggle the&#xA0;cable while observing the box.</li><li style="font-size: 14px; line-height: 2;">Apply firm, even pressure to different areas of the Electronics Box.</li><li style="font-size: 14px; line-height: 2;">Test the box in different orientations and check for bubbles or signs of water entering.</li></ol><h3 style="line-height: 2; text-align: center;" id="why-look-for-bubbles">Why Look for Bubbles?</h3>If air escapes from inside the Electronics Box, this can indicate a potential leak path.As you apply pressure to the box, look carefully for a&#xA0;continuous stream of bubbles from a specific location.This can help identify where water may be entering the box.<h2 id="isPasted" style="line-height: 2; text-align: center;">Check the Electronics Box</h2>Once you have completed the test:<ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Remove the Electronics Box from the water.</li><li style="font-size: 14px; line-height: 2;">Dry the outside of the box thoroughly before opening it.</li><li style="font-size: 14px; line-height: 2;">Open the box and inspect the inside for any water or moisture.</li></ol>Do not assume the box is leaking simply because you see bubbles on the outside. Make sure you have dried the box and confirmed whether water has actually entered the Electronics Box.<h3 style="line-height: 2; text-align: center;" id="if-water-is-found-inside">If Water Is Found Inside</h3>If water has entered the box but you could not identify where it came from:<ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Dry the inside of the Electronics Box completely.</li><li style="font-size: 14px; line-height: 2;">Close the box again.</li><li style="font-size: 14px; line-height: 2;">Repeat the dunk test.</li><li style="font-size: 14px; line-height: 2;">Carefully observe the box for bubbles and inspect the suspected areas.</li></ol>Repeating the test can make a small or intermittent leak easier to identify.<h1 id="isPasted" style="line-height: 2;">Step 2 &#x2013; Test With the Battery Installed</h1>If the Electronics Box passes the initial test without the battery, you can repeat the test with the battery installed if you are troubleshooting water ingress that may be related to the battery or its installation.Only install the battery once the Electronics Box and battery are completely dry.<ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Install the battery normally.</li><li style="font-size: 14px; line-height: 2;">Complete your usual checks to make sure the battery is correctly seated.</li><li style="font-size: 14px; line-height: 2;">Close and secure the lid.</li><li style="font-size: 14px; line-height: 2;">Confirm that the&#xA0;latches are properly tensioned and remain securely closed.</li><li style="font-size: 14px; line-height: 2;">Place the Electronics Box into fresh water.</li><li style="font-size: 14px; line-height: 2;">Give the box a gentle shake to remove trapped air bubbles.</li><li style="font-size: 14px; line-height: 2;">Gently wiggle the cable.</li><li style="font-size: 14px; line-height: 2;">Apply firm, even pressure to different areas of the lid and Electronics Box.</li><li style="font-size: 14px; line-height: 2;">Test the box in different orientations.</li><li style="font-size: 14px; line-height: 2;">Watch carefully for bubbles escaping from any particular location.</li></ol>Pay particular attention to the four corners of the lid, the latches, cable area and sealing surfaces.<h3 id="isPasted" style="line-height: 2; text-align: center;">After the Test</h3><ol data-spread="false" start="1"><li style="font-size: 14px; line-height: 2;">Remove the Electronics Box from the water.</li><li style="font-size: 14px; line-height: 2;">Dry the outside of the box thoroughly before opening it.</li><li style="font-size: 14px; line-height: 2;">Open the box and inspect the inside for water or moisture.</li></ol>If there is&#xA0;no water inside the Electronics Box, the unit has passed this dunk test.<h1 style="line-height: 2; text-align: center;" id="if-your-electronics-box-is-leaking">If Your Electronics Box Is Leaking</h1>If water is found inside the Electronics Box, repeat the test after drying the box and carefully inspect the areas where bubbles were observed.Also check for:<ul data-spread="false" id="isPasted"><li style="font-size: 14px; line-height: 2;">Damaged or incorrectly seated seals.</li><li style="font-size: 14px; line-height: 2;">Damaged hinges.</li><li style="font-size: 14px; line-height: 2;">Bent or damaged latches.</li><li style="font-size: 14px; line-height: 2;">Damage to the lid or Electronics Box.</li><li style="font-size: 14px; line-height: 2;">Issues around the cable entry point.</li><li style="font-size: 14px; line-height: 2;">Debris or contamination preventing the lid from sealing correctly.</li><li style="font-size: 14px; line-height: 2;">Any other visible damage to the sealing surfaces.</li></ul>If you cannot identify the source of the leak, contact the&#xA0;Foil Drive Support Team and provide details of your test, along with clear photos or video of any suspected leak point.

Assist & Assist PLUS – Water Ingress Troubleshooting & Dunk Test

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