ElectricScooterParts.com Support Center

Unfortunately something went wrong with the attachment of your photos because all we can see are the file names of the photos however we can not see the photos themselves.

Presuming that the controller is correctly wired to the power switch, throttle, and motor - the first thing we would do is to disconnect the brake lever switch from the controller and see if the scooter runs then. Sometimes the brake switch will fail and lock into the on position which tells the controller to turn the motor off, disconnecting it will bypass it and allow the motor to run with a faulty brake switch.

If that does not help then the next thing we would do is test the continuity of the power switch and fuse or circuit breaker to make sure they are working properly.

Then if that does not help the next thing we would do is test the Voltage of the battery pack - it should be at around 27 Volts. However even if it is at around 27 Volts it is not in the clear yet because it could be dropping Voltage under load which is causing the speed controller to not operate the motor. The controller needs to see at least 23 Volts when the battery pack is under load in order to run the motor. Here is a link to our battery pack load testing guide: https://www.electricscooterparts.com/loadtest/index.html

Connecting the battery pack to the motor only proves that the motor works and does not indicate that the battery pack is working properly because the motor will run at any Voltage and will not indicate if the battery pack is dropping too much Voltage under load.

If the brake switch, power switch, fuse, and battery pack all test good then the next thing to test is the throttle. We have a throttle testing guide at this link: https://www.electricscooterparts.com/throttletestingguide.html

If all of the above parts test good then please let us know and we will take it from there.

I found your photos from a topic that you created a couple of days ago. I will delete that topic because it is the same as this one, however I will insert the photos from it here.

Those look like the original batteries so I would not have too much faith in them maintaining their Voltage under load. Only a load test will determine if they are good or bad though.

Maybe the photo is hiding a wire because the throttle only looks like it has two wires to me. The SPD-24250B controller requires a three wire throttle. Hopefully the throttle has a green wire that I am not seeing though.

The SPD-24250B controller will not work with a two wire throttle, it does require a three wire throttle to operate. The two wire throttle could possibly damage the controller so I would wait until you have a three wire throttle before resuming the conversion.

The Hello Kitty City electric scooter has a 24 Volt battery pack made from two 12 Volt batteries, so I presume that the battery pack you received is wired for 24 Volts, or that you received a set of two 12 Volt batteries.

Each 12 Volt battery should read around 13.8 Volts after it has been fully charged. If they are new and have not been charged yet then they might be a little under 13.8 Volts. If they are in a pre-wired to make a 24 Volt battery pack then the Voltage of the battery pack should be around 27.6 Volts (13.8 x 2).

These are the Voltages that the batteries should be around when they are not connected to the controller, or when they are connected to the controller and the power switch is off. When they are connected to the controller and the power switch is on, the Voltage should be the same, however when the throttle is fully engaged and the motor is running their Voltage should drop just a little (1/2 to 2 Volts).

Please let us know if you have any questions.