My controller stopped working any advice

[fancyfish]

Hi I have a 7091 single controller that is no longer changing from my upper and lower settings. The pump is still working and the power light is on but it will not oscillate from high to low. any advice on how to fix this?
thanks
Pam

 

[rvitko]

Three things to check-

If a photo cell is connected make sure it is not in a dark place.

If no photocell is connected check the plug where the photocell would connect for salt creep or water damage.

Make sure the pulse knob is not turned fully clockwise (pulse off)