Esc won't power on with sensor lead connected?
 

Right. I've a strange problem, which I'd be grateful of any advice on... I'm just shuffling motors and esc between cars, and the toro 120a esc will not power up when the sensor lead is connected to the motor. If I disconnect the sensor lead from the motor, the esc powers up fine. I have tried it with another motor, and it powers up fine when connected...
So it would appear to be the original motor that's the issue, but what would be the fault?
Can anyone help please?
Thank you.

Many modern ESC will run a sensored motor as unsensored if the sensor lead is not connected. If the sensor board in the motor is broken it would confuse the ESC with the sensor lead plugged in hence not running. If you do not plug the lead in it will switch to unsensored mode and run the motor that way. If you have a known working sensored motor, you can try that to see if it is the sensor lead that is damaged or the motor. If the motor then you may be able to replace the sensor board in the motor.

Thanks for that. I've not sen this fault before, but given that it works fine with another motor, i did suspect the sensor board.

Sadly it turns out that this particular motor has a sensor board that is (or at least was!) soldered to the motor innards.

Never mind! We live and learn...

Tim, Have you got a "Core RC Sensor Widget" (If you'll excuse the question!)

you plug it into the sensor port of the motor and when you rotate the motor by hand you can see whether the sensor board is working correctly.

If you don't they are only ~£10-15.

I have one you can try, but am not down at Batley for next few weeks due to cub camps and other family stuff

Chris