i have a 97 f150 , sometimes power windows will work, sometimes they don.t. sometimes when i turn the key on they work and then when i start it they quit.
Check the main door swicth for loose wire,s,all so look in side the door jam where the harness goe,s in to door,may have a pinched wire.
"Sometimes" problems, especially electrical, are almost impossible to detect. Removing the door panel and "wiggling" the connections is about all one can do. That, like TST stated, is checking for obvious pinched wires.
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