he became deaf in Hawkeye v1 #4
which lasted around 15 years (in which there were only about 10 references to his hearing loss- i could post those panels if you want)
until, after some extreme 90s alt-universe event where all the heroes ended up dead,
the “heroes reborn” universe, where the panel above is from
he was revived in 1998 with completely restored hearing
it’s shown that he knows sign language when she-hulk attempts to unsubtly warn a revived hawkeye (after he died in avengers disassembled, not heroes reborn) of his impending doom
but he was napping in the jury
now, clint’s been deafened again in #15 of the current run of hawkeye
and it seems it’s being retconned that clint had actually been deaf for a time in childhood, before he sacrificed his hearing in hawkeye v1
Great recap of the Hawkeye deafness (yay comics timeline!)
Tumblr Exodus 