My first experience was while my 21 was still under warranty, the LED was fried. My service guy just replaced the light under warranty and transfered over the BLIS sensor. Now that light has moisture in it again but not as bad as the other one. The drivers side was full of water so I removed it from the truck to fix. I pulled off the BLIS sensor so I could have an opening to use a hair dryer to get rid of the moisture.

I was pretty disappointed when two of the four attachment points for the BLIS were broken and two pieces of black plastic that looked like a cap was broken in the light. The actual BLIS unit has about a 1/2" gap, there is an orange gasket but I assume water may have been entering there. I used 5 min epoxy to fix the attachment points, applied black silicone to seal the gap between the red lens and the black housing, and add strips of Zip tape around the perimeter of the BLIS sensor. Washed my truck and so far so good, now I have to do my passenger side.

I am in FL and my truck is outside in the sun all day so I guess plastic fails after 3 years. Is anyone else getting moisture in their taillight?

 

So far no moisture in mine, truck is outside 5-6 days a week depending on the season. Good info on the fix.

 

All the lights worked except the led running lights. I had to purchase a new BLIS Module with the harness. This made the led's to work but The new BIS module causes a fault, you have to have it calibrated at the dealer. I swapped my old BLIS sensor to the new assembly and everything works.

I did notice as well the black housing of the tail light has a large crack. Everything in this tail light thats plastic is cracked. The plastic is really brittle. Pretty bad for a 70K + truck. Truck was built during covid so not sure if ford sourced from other manufactures and they used inferior plastic.