Bottom barn doors do not open

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You should be able to remove the trim from inside, The trim at the top edge has clips and pulls straight up to disengage them. The panels then pull free with 9 door panel trim fasteners. That will give you access to the latch assemblies and you should be able to determine if the cable broke or it's something in the latch. A lot of times I've found them rusted real bad and cleaning them and using some silicone grease frees them up.