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Electric Scooter controller clicks but doesn't run

Just replaced the controller(new). It clicks when throttle is twisted but motor doesnt run. Battery checks out ok 26 volts. Measured output voltage from controller with motor connected and disconnected and zero volt. Measured ohmic reading of motor and its 7.5 ohms. Break lever switch is ok and so as the reset switch and power on switch as well. Any idea what should I look at next?

That type of clicking controller problem is usually caused by an old or worn out battery pack that drops too much Voltage under load.


To load test the battery pack test its Voltage with the power switch off, and then while watching the Voltage level turn the power switch on and twist the throttle. If the battery pack Voltage drops to 23 Volts or less then the battery pack will need to be replaced. A good battery pack will drop less than 1 Volt while under load. Controllers turn off power to the motor when they detect a battery pack Voltage of between 21.5 through 23 Volts.


If the battery pack passes the load test then please let us know and we will take it from there. Please let us know if you have any questions.

Performed load test on battery pack and it's good. It dropped from 24.52vdc to 23.91vdc. What is the ohmic value of a good motor? Mine read at 7.5 ohms.

We do not have any specifications for the proper resistance value of electric scooter motors, The motor's resistance should vary widely depending on the position of its shaft so that could be a difficult value to determine with certainty. We usually test motors by wiring them directly to a battery or battery pack to see if they run.


The 24.52 Volt battery pack Voltage is very low as it should be between 27-28 Volts after being fully charged. Each battery should recharge to and maintain a 13.8 Volt charge. Although the battery pack did not drop lower than 23 Volts during the test I would still be suspect of it since it is not holding its charge. It could be possible that the controller has a higher low-Voltage cut off value than normal, so I would inquire with the seller of the controller to see if there is a specification sheet available for the controller which states what its low-Voltage cut off value is.


Although it is rare, some controllers use brake switches with normally closed switches, so you might want to try bridging the brake switch wires together on the controller and see if that helps.


Also, some scooters require to be moving before the motor will start, so I would try kicking the scooter off to over 3 mph and then see if the motor will start while the scooter is in motion.


Please let us know how it goes.

Thanks for the technical help. Really appreciate it. After charging the batteries for 8 hours, load and no load, the batteries stayed at 27 VDC. Directly wired the motor from battery and it ran fine. Throttle switches are good(orange and brown) they both open and close accordingly. Break switch is normally closed and it opens when brake lever is pressed. The controller clicks once I twist the throttle but there's no output coming out( yellow and blue wire. Under voltage setting for the relay is set at 19vdc. I would assume I was sold a bad new relay.
Additionally, I performed the 3 miles per hour test to activate the motor and still didn't run.
It sounds like you may have a Razor E100 series scooter. If it is a Razor E100, E125, E150, E175, eSpark, or Launch then those models do need to be kick started to above 3mph while twisting the throttle to engage motor. You might want to try kicking it up to over 5 mph to see if it starts then.

The controller will not output any Voltage to the motor until the scooter has been kick started and it begins to run.

If you have not already done so then I recommend to unplug the controller from the battery pack and test the battery side of the connector to make sure that there is Voltage present at it. If the battery pack wiring harness connector has Voltage then the battery pack wiring harness and circuit breaker are both good.

Also if the switch has not already been tested for continuity then I recommend to unplug the switch from the controller and test it for continuity. The controller connects to the two silver color switch terminals, and the charger port black wire connects to the brass color switch terminal. Razor scooters are tough on their switches so that is a good part to double check for proper wiring connections and continuity.

A final test that we would perform before replacing anything is to individually load test the batteries for 15 seconds with a load that is three times the Amp-hour rating of the battery. An automotive carbon pile load tester works great for this. The Voltage should not drop under 12 Volts per battery during this test. Battery stores can also load test the batteries if necessary.

Please let us know how it goes.

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