Code 81 strikes again!

After reading up on this forum I am seeking advice mostly on where to buy a new speed sensor magnet. The magnet has a single crack and was found with a nice layer of magnetized grease chuncks stuck to it. Last pic shows my failed attempt to clean the magnet in hopes that it would start working. I did not think to glue the magnet down at the time. At this point I want to buy a new magnet if available.

Any GEM dealer, nev parts, some EZ GO dealers, Ebay.

This is the one I bought. Never installed it but it looks right. I can check the fitment on a motor later today if you need me to.

Over time, the magnetic ring is losing power. The hall sensor is not defective. You need to make your magnet. I made wheel from 5mm polycarbonate and 4 small neodymium magnets. It is important to understand how the polarity of the magnet triggered the sensor. And POXIPOL )))

As a temporary solution I did so. It hall sensor from old gazoline auto.
There is only one subtlety. This sensor should be powered from 5 volts. If it is powered from the red wire in the regular hall sensor, it will give 12 volts to the motor controller. How he would react to this I don’t know. The simplest solution is to put before the new hall sensor to the red wire of the IC 78L05 or 7805.
It is worth noting that I have a slightly different type of hall sensor.