T4 & T3 Controller Beeping during acceleration

T3 and T4 Controller begins to beeping around the 19 to 20mph point, then stops after it exceeds the 20mph, when I then let off the accelerator and the mph drops down to the 20mph it begins to deeping until it gets below 19mph and then no noise.
It does not do this with my original 5hp motor, only when I have the 7-1/2hp Ride4Fun motor, I purchased a 7-1/2hp motor from Rodney, it does the same thing.
Last week during regular driving my T3 Controller error code 66 with the 7-1/2hp motor on it, switch to the 5hp, controller still shows error code 66. I switched the T3 out with my T4 controller and no error code.
Anyone ever heard or had this problem of the Controllers beeping very quickly at the 20mph area but then no noise before or after that speed?

Interesting/very odd.
Your description says it did this from a T3 controller, then again for a T4 controller?
Is this repeatable? Like every time you hit 20?

I don’t think the controllers have any beeper components inside. I doubt it is coming from the controller.

The only things that will beep is the PSDM (steady beep if park brake is down and Key switch OFF) and (Beep, Beep when in Rev), and the turn signal warning when on too long. Neither one is related to speed bracket of 20.

What other accessories do you have mounted on your car that is not stock?

To track this down perhaps you should jack up the front end and run the car in place. See if it will beep at your 20.

(Odd thought) → Are you running some sort of GPS app on your phone?

Only beeping whenever I have either of my two 7-1/2hp motors on it, nothing when the original 5hp motor is on it, no matter how hard I push it. When reversed it use to beep loud, now it’s more faint of a beeping, e-brake down it’ll beep also as you said.

After the error code 66 on the T3 the other day, I’m just worried I’ll lose my T4 controller if I can’t figure it out.

So- prove to me that the controller is beeping.

Record what you are hearing while driving and post a link to it here.

Does this beep sound anything like the other beeps in the car?

What other aftermarket accessories are installed on your car?

If it is truly a speed related thing (~20mph according to your dash display?) then it will happen while running in place. If yes, then have someone maintain that speed and go up front where the controller is and verify that it is truly coming from there.

Will do, appreciate you taking the time to help.