The first thing to try is to clean the 'stirrup' on the shoulder belt. Get some rubbing alcohol, a cloth rag, and an old credit card. Saturate the cloth with the alcohol, cover the card with it, and force it into the stirrup (on both the top & bottom) until it no longer comes out dirty.
Next, clean the surface of the belt webbing with the alcohol soaked cloth.
If it doesn't slide nicely after that, some folks have had success by rubbing the inside of the belt with Ivory Soap. Not too much, you don't want it to get on any clothing.
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If this 'maintenance' doesn't work, you may need to call Honda customer service to see what they can do. I found this information on the Web:
Next, clean the surface of the belt webbing with the alcohol soaked cloth.
If it doesn't slide nicely after that, some folks have had success by rubbing the inside of the belt with Ivory Soap. Not too much, you don't want it to get on any clothing.
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If this 'maintenance' doesn't work, you may need to call Honda customer service to see what they can do. I found this information on the Web:
Source:U.S. Models
Honda provides a lifetime warranty on seat belts. Honda will repair or replace any seat belt component that fails to function properly during normal use. Please see your Honda Warranty Information booklet for details