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Wiring a CT-660B9 and a THR-74 Throttle

I recently ordered the CT-660B9 controller along with the THR-74 throttle from you guys and i'm having trouble wiring this all together. Now the wire colors are different from the Controller to the Throttle which i believe i have accounted for but cant work out why this is not running the motor. 

I have the motor and battery connected, running the 36v.

Current Wiring: 


Controller Red - Throttle Red 

Controller Black - Throttle Black 

Controller Green - Throttle White

Controller Yellow - Throttle Green

Key Switch

Controller White - Throttle Yellow

Controller Yellow - Throttle Brown

The key switch works fine, and i can run the motor if i short the throttle connections (white and green throttle wires) and get full throttle when i turn the key switch, but cannot get the variable function. 

Hope i have explained this well enough, could you give me a wiring diagram. The next step is going to be checking on a volt meter as seems the signal wire on the throttle may not be working?

Appreciate any help.   

It sounds like you have it wired correctly. Here is the wiring diagram.


There might be a connection issue between the controller and throttle wires so I would check all of the connector terminals to make sure the wires are properly attached to them.

Shorting the throttle's green and white wires would send 36 Volts to the throttle's hall effect sensor signal lead which could burn it out. These type of hall effect sensors are extremely sensitive to miswiring and can not handle over-Volting or reverse polarities very well. I am not sure if the controllers green 1-4V signal input wire can handle a 36 Volt signal either.

The controller can be tested by unplugging the throttle from it and bridging the throttle connector's red and green wires together. If the motor spins during this test then the controller should be fine.

The throttle can be tested by having it connected to the controller with the power switch on and reading the Voltage between its black and white wires. There should be approximately 0.8 Volts and 4.2 Volts between these wires depending on the position of the throttle. If there is no Voltage between the black and white wires then test between the red and black wires to make sure that the controller is outputting 5 Volts to the throttle.

Please let us know how it goes.


thanks for the reply, double checked and its all wired correctly as per the diagram. 

also checked the controller by bridging the Green and Red and that spins the motor fine so its not the controller - seems the speed control wire on the throttle is the issue as I'm not getting any read no matter what position the throttle is in...

Please advise.

Is there anything you can do in terms of a return/exchange or am I going to have to purchase a complete new unit?

Shorting the white and green throttle wires together will send 36 Volts to the throttle's hall effect sensor and burn it out. The throttle is a sealed part that can not be repaired and would need to be replaced with a new unit.

I recommend sending a message to our customer support team explaining what happened. I will have a talk with them and let them know about this and they will be able to help you from there.

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