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Rad City 5 Plus - no throttle - no power

Started by gregroe, July 02, 2023, 09:11:05 PM

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My rad city 5 plus 2021 powers on but there?s no power in throttle or power assist . It was working ok for a while then it seemed slow/sluggish then no power at all .  I took it into rad service and they said they fixed a wire/ sensor to brake. Took it home it worked one time then again the throttle and power assist stopped working

Any ideas?  Bad controller? Sensor?


No error messages? Have you tried disconnecting/reconnecting the brake switch cable or the main connector to the motor?


I agree with Suspci, and the symptoms sound like a brake cutoff system. Disconnect both brake sensors from the levers and give it a try. Another way of checking is your brake light: It should come on when you squeeze each of the brake levers. If the brake light stays on when you are not pulling the brake levers, your brake cutoff sensors or their wiring is at fault. If the brake light does not work at all, this will also cause the pedal assist and throttle to not work. Disconnect the taillight to diagnose this. A blown taillight/brakelight makes the controller think the brakes are on.


The wife's brand new 2 week old Radcity 5 Plus with 16 miles had the no PAS/throttle issue. Worked perfectly before that until it didn't.  Double-check all connections, brake lights, brakes, etc...  All displays worked as normal with no error codes including showing mph on speedo when spinning the rear tire by hand.  Trouble-shot with Rad chat and they eventually sent me a new controller.  A real PITA to change out the controller; but, resolved my issue.
2023 Himiway Cobra Pro, two 2018/2023 Radcity Step-Thru, & two 2016 Radrovers