Casio CZ/ VZ/ FZ - Pro Series

Though the guts are basically the same in all the CZ series, I doubt the parts placement is. At least in the CZ-3000, (with the board in front of you, keys closer to you, as if playing) I believe the relay is toward the rear on the left, at the rear of the lower circuit board. But that's where the line out & phone jacks are on the larger CZs. For the 101, I'd expect it would be near those same output jacks on the side right. I'm not certain but I think there is only one relay so if you locate any relay theres a real good chance you've found the right one.