How to split the MP hub

[sveinf]

Hello, I`m a beginner here and tries to do some faultfinding on my brand new MP. (Take a look in the topic "Three beeps from the MP") My single question is now; How to split the MP-hub? Can anyone give me some goood advice here? Photos/illustrations will be highly appreciated!

[Bikemad]

Svein,

You might want to check out this post.

Alan
 

[sveinf]

Hello Alan
Now I`ve split the hub and measured the cables, no broken cables found. However there is a difference in the cableconnection to the controllerboard. As you can see the yellow and white cable is connected otherwise than the same in your photos. Can this be the source to my problem?

BR
Svein

[Bikemad]

Your wiring appears to be fine.

The yellow lead (which is not connected on mine) is connected correctly on yours.

Your white throttle signal lead is also connected correctly.

Put the hub back together again and check that the voltage between the red and black throttle wires is ~4.9V.

Check the voltage between the white and black throttle wires, it should vary between ~0.8V with the throttle released, to ~3.6V at full throttle.

If the voltage measured on the red wire is ~4.9V, but the white throttle wire remains below 0.5V, this would cause the three beeps indicating the throttle signal voltage is too low, because your throttle has failed or has possibly been damaged by being incorrectly connected at some point.

You should be able to check the controller is working correctly by disconnecting the throttle and then connecting the red and white wires (from the motor's harness) together, and your motor should then run at full throttle.

I hope you can understand these instructions, but if they are not clear enough, please let me know.

Alan
 

[sveinf]

Thank you for the new checkpoints. I`ll give it a go this evening!

Svein

[sveinf]

Hello again!
Now I`ve done some measuring, and the result was as follows:
Voltage between red and black throttle wires: 5,12 V
Voltage between red and white throttle wires, released and full throttle: Both about 2 V
Red throttle wire: 5 V
White throttle wire: below 0,5 V

But also:
When first disconnecting the throttle, and then connect the red and white throttle wires, I was ready to conect the battery with the key to see if the motor would start. No reaction whatsoever....

The cruisecontrol button still give steady half speed when pressed.

SO....whats next?
Is this meaning that both throttle AND controller are broken?
Could we say that the

[Bikemad]

Svein, I think I've discovered why it did not run with the red and white wires connected.  I've just tried connecting my battery with full throttle applied and nothing happens on mine either. If I then release the throttle and twist again, it works fine.

It would appear that the Pie's controller has a built in safety feature that prevents it from activating the motor if the power is turned on with full throttle applied, just like some of the speed controllers used on R/C Models.

Try disconnecting the red and white wires, turn on the battery first and then touch the red and white wires together (with the wheel off the ground) and I think you'll find the motor will then run at maximum speed.

From your description, it definitely sounds like the throttle control is damaged, but I think you will be able to prove that the controller is still OK.

Give it a try and see what happens.



Alan
 

[Leslie]

Svein, I think I've discovered why it did not run with the red and white wires connected.  I've just tried connecting my battery with full throttle applied and nothing happens on mine either. If I then release the throttle and twist again, it works fine.

It would appear that the Pie's controller has a built in safety feature that prevents it from activating the motor if the power is turned on with full throttle applied, just like some of the speed controllers used on R/C Models.

Try disconnecting the red and white wires, turn on the battery first and then touch the red and white wires together (with the wheel off the ground) and I think you'll find the motor will then run at maximum speed.

From your description, it definitely sounds like the throttle control is damaged, but I think you will be able to prove that the controller is still OK.

Give it a try and see what happens.



Alan
 

A few controller have this function.  It is a very sensible thing to do.  We were discussing in another thread the test to make sure your controller is good by shorting t1(5v) and T2.  It was mentioned the controller had to be on first.

I have a controller here above mentioned test wont work whether the controller is already on or not, I think :/..  Its not GM either.

I wanted to know what was the go here!

Does shorting T1 and T2 when the controller is on already make the wheel spin at full, or is this just when power is turned on the safety function activates?

Thanks. 

[Leslie]

Hello again!
Now I`ve done some measuring, and the result was as follows:
Voltage between red and black throttle wires: 5,12 V
Voltage between red and white throttle wires, released and full throttle: Both about 2 V
Red throttle wire: 5 V
White throttle wire: below 0,5 V

What's the volts between white and black twisting throttle?

[sveinf]

Hello again!
I did it the described way, and the motor stated to run for full speed! So the controller is OK, I presume.
When twisting the throttle there were almost no difference I voltage between full and no throttle.
Ca 2 V.

Is it possible to get a new one from GM? They don`t seem that cooperating...

Anyway great thanks to Alan!

[Bikemad]

Svein, it would appear that your controller is OK, but unfortunately the thumb throttle is not.

You will need to email Tom again (zhourenli@goldenmotor.com), but his English may not be as good as yours, so keep your message short and easy to understand.

Alan
 

[sveinf]

Will do!
Thanks again for good help!

Svein