Did you verify they worked when you picked them up at the repair place, before you brought them home? That's always a good idea, especially when you have a long trip.
Odd that both would develop the same problem on the ride home. I'm wondering if the repair work was not completed or something was left undone, not connected, etc. Might be worth a call to the place you had the work done, surely they stand behind their work, they know what was just done to the machines and could give you tech advice specific to that.