Spa pump won't switch to low power speed

i have a hydropool 575 hot tub it is quite old the pump which is a two speed is only working at high speed and will not go back to low speed. it was working fine last night. i have shut off all power to see if it would reset and it has not how do i fix this. also we had a lightning and thunder storm last night could this have done something i am not mechanically inclined so please help in easy to understand steps
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.