It appears to be a convenient device for switching between the "Freedom" and "Mild Hill" modes, but the performance claims are misleading.
The four PDS modes have different top speeds and/or different amounts of regen braking. (See attached)
However, the torque is the same in all of them. Or at least I could not detect any difference on a 30° incline in the two modes I used.
I just added a SPST switch I had laying in my junk drawer to the jumper wire between pins 1 & 5 (See second attachment) to get the Freedom and Mild Hill modes.
I did have to stop, get off cart and lift the seat to change modes, but the cost was $0.00 plus my labor.
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The apparent increase in torque is due the the PDS controller limiting the motor RPM by reducing the duty cycle of the PWM DC that is fed to the motor. When the motor RPM drops below the max RPM of the mode it is in, the duty cycle is increased to return it to the max RPM. (Basically, it acts like a cruise control or speed governor when the pedal is on the floor)
Since the Motor RPM is limited to a lower RPM in the Mild Hill mode, A steeper incline can be climbed before the cart starts to slow noticeably.
Max motor is limited to about 4,400RPM in Freedom, about 3,300RPM in Steep Hill and about 3,100RPM in the other two modes.
On stock height tires (18"), that translates to roughly 18.5MPH, 14.5MPH and 13.5MPH.
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Another bit of misinformation is the warning about going downhill in the "freewheeling" mode.
A PDS controller does not have a "freewheeling" mode, but one of the two modes the gadget will select does not have regen braking when you lift your foot off the pedal.
However, the PDS controller does limit the top downhill speed in all modes with regen braking, to about 2MPH above the top level ground speed for that mode.
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Convenient = Yes
Nice looking = Yes
Easy install = Yes
Magic = No
Worth the money = Up to you. (If I was going to continue using a PDS controller, I would probably buy one.
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