I bought a used hot tub about a month ago the control panel of the hot tub is a Spavision Supra series so I assume this is also the name of the hot tub. The problem I am currently having is the dual stage pump is not turning on high when I push the air switch. Because the pump is not turning on half of my jets are not working. I opened up the control panel and tested the air electrical switch inside the box and everything appeared to be working correctly. What do I need to do to get the pump to switch to high speed so my jets will operate. Also do you have a wiring diagram for the control box of this particular hot tub the Model # is AS400-2020 the serial # is 980G08-26?

The solenoid that rotates the cam on the mechanical switch may be sticking or rusted. Some spas use an air operated cam switch, others use a normally open momentary contact air switch that cycles a solenoid. It sounds like you have the latter, so look for a solenoid with a stuck plunger