Fault finding help

[iain85]

Nearly one month later!

Ok so after managing to disassemble the throttle I located the hall sensor. I didn't realise how tiny it was! There is no noticeable damage to the wire connected to it although due to its size I couldn't be sure. Is there any resistance checks I can make to determine a dead short?

 

[Deleted member 4366]

To test it, apply 5v to the red and black wires (red +ve). Measure the voltage between the black and the third wire. It should be about 3v. Wave a magnet around it and you should see the voltage change.

 

[iain85]

Damn,

So I received a new throttle kindly sent by Alex on here. I plugged it it and still no joy. The new throttle has two additional wires soldered together , any idea what these are for?
Also what's next to check ?

Cheers

 

[103Alex1]

It is this throttle if that helps - anyone ??? I never fitted it (used thumb throttles instead) so don't know how it wires up, but presumably the fact it has LED voltage level display is the reason for extra wires ?

Half Twist Throttle with LED Voltage Level Display - BMSBATTERY

 

[iain85]

Cheers Alex, there is 3 extra wires, 2 which have been soldered together and a loose yellow wire. I've worked out the yellow is for the battery indicator but am unsure of the other two.

 

[Zebb]

Cheers Alex, there is 3 extra wires, 2 which have been soldered together and a loose yellow wire. I've worked out the yellow is for the battery indicator but am unsure of the other two.

If you look at this thread Dave shows how this throttle is wired up, I think its the same one.


Link. http://www.pedelecs.co.uk/forum/electric-bicycles/15762-throttle-wiring.html#post193311

 

[iain85]

Thanks Zebb. I think the brown and green and been soldered together to bypass the switch.

Must not be my throttle at fault as this one is brand new, where next should I check?
Thanks,

 

[103Alex1]

Have you tested the MOSFETs in the controller to check they are not blown ?

 

[iain85]

Hi Alex, how do I check the mosfets?

 

[103Alex1]

Hi Alex, how do I check the mosfets?

I have never tried to test them but it looks easy to do from ES search if they are loose components. However looking at ES threads it is not so straightforward if they are installed on a PCB.

As they are installed to the PCB one of these will likely tell you whether the controller is blown and test a lot more besides :

New Brushless Motor Controller Tester for 24V 36V 48V 60V Electro Car Scooter | eBay

It's all down to urgency - can probably post you mine to use if you are pressed for time to get things fixed but would appreciate it being returned soon as poss.

 

[iain85]

That is very kind of you. Would it be easier if I posted you my controller?

 

[103Alex1]

That is very kind of you. Would it be easier if I posted you my controller?

You can do, although if it comes up clear you can also test the motor phase/winding, halls etc using the same device and it might be easier / more efficient to test everything at once rather than doing it all piecemeal.

 

[iain85]

I suppose that makes more sense. Are they fairly straight forward to use?

 

[103Alex1]

I suppose that makes more sense. Are they fairly straight forward to use?

It comes with instructions which I can send over and recommended by d8veh and others for simplicity. Looks straightforward to me and very clearly labelled up with Bafang-compatible connectors. I haven't had to use mine because (without tempting fate !) I haven't yet had cause to ! Just wanted to have one to save messing about if anything goes wrong before I get hold of a car as back-up .

I got it because it seemed user-friendly enough to do stuff which would otherwise have me asking endless questions and fiddling with multimeters trying to do things the 'long way'. Don't understand enough myself without having my hand held and learning as I go without a plug & play device to "cheat" with !

 

[iain85]

Despite being fairly practical, electronics blow my mind and any handholding is more than welcome! : )

Cheers Alex that would be great. Do you still have my address?

 

[103Alex1]

OK - yes, I've still got it.

 

[iain85]

Thanks let me know how much postage is.

 

[iain85]

Hi Alex,

Many thanks, I've received the tester this morning just before work. I've popped home for lunch and had a quick look at it. Assuming I've understood the terminology/ instructions correctly I think I've blown the controller

Just to confirm the steer is the throttle. This light goes from green to nothing to red when turned through its range?
I'm getting the middle led on the right flashing to confirm 5v output but no sequence of red lights on the circle of LEDs do I think the controller has had it according to the instructions. Il have another look at it this evening and try to test the other components.

Thanks again,

Iain

 

[Deleted member 4366]

You didn't post any pictures like I suggested in post#13!

 

[103Alex1]

Sounds like you're narrowing it down. When you've run the tester tests and isolated where the problem lies (or problems) to a component then I'm pretty sure d8veh can help you determine whether it is fixable or not, what's involved and whether economic. May need to do further stuff but at least you will be looking in the right place.

But do follow any of his step-by-steps to the letter - it's the best (only) way to go .