The cruise is complex and involves a lot of different components. I would imagine the factory manual has a large chart with many pages to walk you through it. Off the top of my head you have;

The switches and the brushes behind the steering wheel

The switch on the master cylinder and the brake pedal

The vacuum dump valve on the brake pedal

The brain

The vacuum servo and it's vacuum lines

The speed sensor input

 

Thanks. Brake lights work properly, so I'm comfortable ruling the pedal switch out.

Looking around online, next logical (and easiest) thing to check is probably the switch and harness at the MC.

Mike