Green’s Dictionary of Slang

1. a difficult situation.

1887		G. Devol Forty Years a Gambler 19: Then I commenced to think about getting out of that hot box.
1901		S.E. White Westerners 126: We got here a little late, boys [...] on account of a hot box, but here we are.

2. a tantrum.

1883		G.W. Peck Peck’s Bad Boy and His Pa (1887) 40: If he got a hot box, and flew around mad, he was better out of church than in it. [Ibid.] 148: When [...] Pa found that I had not carried in the kindling wood, he had a hot box, and he told me if the wood was not in when he came back from the lodge, that he would warm my jacket.
1905		G.W. Peck Peck’s Bad Boy Abroad 129: Dad got a hot box, like a stalled freight train.