Joe,
If no one has changed anything the plug is wired: #1 has one power wire and one foot control wire, #2 has the other
power wire, and #3 has the other foot control wire.
The receptical on the machine is wired: #1 has one wire from the light, #2 has the other wire from the light and a wire from the motor, #3 has the other wire from the motor.
This is standard on White brand machines and White made Kenmores. Some times they are labeled BLK/ BLACK (#1), RED (#2), and WHITE(#3).