Freddie Prinze (Sr., obviously) blew his brains out during the run of “Chico and the Man.”
One episode that dealt with Chico’s dad (played by Cesar “The Joker” Romero), with whom he had not had any contact since he was four, reappearing in Chico’s life. Chico’s dad had done really well for himself, and had spent many years trying to track Chico down, since every letter he had ever written back to his family had been returned unopened.
Chico’s dad wanted him to come back to Mexico with him, and work in the shrimping business with him. Chico, obviously, had to tell him, “No,” that this (Los Angeles) was his home and Ed and Louie and all the rest were his family now.
But, the others weren’t so sure about it, and Louie (Scatman Crothers) makes a comment to Ed (Jack Albertson), concerning the fact that Chico might leave with his dad to Mexico says, “We could lose him forever!”
That was the very next ep that aired after his suicide.
During the rolling credits at the end, they had dubbed a very voiceover by a cracking-voiced Jack Albertson, appreciating all the letters and condolences that the cast had received on the behalf of Prinze.
There were several eps left with Prinze still in them, and they just finished the last several without Prinze. Don’t remember if they explained it.
However, the next season, they introduced a new “Chico.” Not the same character, but as Ed says, “You’re all ‘Chico’ to me.” Later in the season, new Chico asks Ed about the “other” Chico that he keeps hearing about. Ed just tells him, “He went away.” (Although it seemed as though in an earlier ep either from the end of the previous season or the beginning of this one that Ed said that Chico had gone back to Mexico.)