Help - My pedelec is not working

cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
179
www.whatonlondon.co.uk
Today I hit something with my speed controller and it was completely detached from the bike:


Here is how I fix it back.

But now, the pedelec is only at the lowest speed, I'm litterally running at 10km/H :(

I tried to see what happened inside:


It seems that the green cable has been disconnected. I'm not sure however. And I don't know what I should do.

Any thought?
 
D

Deleted member 4366

Guest
It seems that the green cable has been disconnected. I'm not sure however. And I don't know what I should do.

Any thought?
It's difficult to see in the photo because it's a bit fuzzy, but can't I see three pads: one with the white wire attached, one with the red wire, and one in the middle with nothing. I guess that's for the green wire, so solder it back on if you know how to solder, otherwise get somebody that does to do it for you.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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www.whatonlondon.co.uk
I know. I've got my previous phone stolen so I can only do crappy pictures with my actual phone.. Waiting for the iphone 5..

For the green wire, I don't know how to solder, but I did it when I was in high school. Maybe I can still do it now.

Problem is that I don't know where the green wire should be soldered...

Gonna ask the seller.
 
D

Deleted member 4366

Guest
You shouldn't attemt to solder it unless you'e sure you can do it right - better to find someone that can do it properly. It looks like the green wire should be on the pad between the red and the white wires.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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It's not very clear (actually it's not clear at all), but there is 4 wires. In the middle there is a black wire. That's why I don't know where should the green one be solded.

Why shouldn't I solder? It shouldn't be too hard?
I just purchased that on ebay:
Variable Temperature Soldering Station Iron Kit
 
D

Deleted member 4366

Guest
Ok, I can see the black wire now that you pointed it out. We can apply a bit of logic. Each of the pads to which the red, white and black wires are connected to appear to be marked with a letter or something. The photo isn't clear enough to show what. So there should be another marked pad somewhere nearby. I need a clearer photo to be ablt to help you.

I teach electronics at school and most of the kids don't take any notice of the techniques that I teach them to get a good solder joint. I wouldn't trust many of them to do an important joint, but I bet they would all have a go at it. That's why I'm a bit negative. It isn't just a case of bringing the iron and some solder to the joint. If you feel confident - go for it.

Here's the basic technique:
Bring the wire to the pad and keep it there while you heat both the pad and the wire with the iron for several seconds.
Keep the iron still, while you feed in a bit of solder
Keep the iron still for a few seconds after stop feeding in the solder
Remove the iron, but keep the wire stationary on the pad
In principle you shouldn't move the iron at all during the process until you finally remove it.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
179
www.whatonlondon.co.uk
Thanks d8veh. I'll wait tomorrow to see what Conhismotor seller tell me. Maybe take a better picture at work tomorrow. I can't do anything better with my old phone.

For soldering, I'll try to practice a bit on something before. Just to make sure I don't do anything wrong. I think I just have to make sure the solder doesn't expand too much. Otherwise I'll have to change the complete speed controller.. And I'll be very upset.

Finally, since I've got my bike, it takes a lot of time to make it work and repair it. I'm on my way to purchase a lot of tools! :D
 
Last edited:

johnc461165

Esteemed Pedelecer
Aug 19, 2011
546
22
WN6
Looking at your photo the green wire is so short that it will only reach certain solder points, get a good magnifying glass and check for odd solder spots, the wire is so short it can't have moved far from it's original position
 

cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
179
www.whatonlondon.co.uk
Thanks John. My actual problem is that I can't see where it was soldered before. I'll try to get a picture as soon as possible.

And my seller Conhismotor is not answeriiiing... my god, I hope the 2 years warranties were not just lies... :(
 

cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
179
www.whatonlondon.co.uk
It's me again.

The pedelec is still not working properly (since last month). Here is a better picture:


Any idea how to fix the pedelec? (the throttle is still working)
 

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
The pedelec sensor is normally fed to the controller, have you checked the wires going to it from the sensor?
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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179
www.whatonlondon.co.uk
Yes, it's connected.

The strange thing is that the pedelec is working... but stuck to the lowest speed. So the sensor is correctly connected.

I suspect it's the green cable from the speed switcher that's has to be solded. But I'm not sure and I don't know where.
 
D

Deleted member 4366

Guest
The only logical place for the green wire is to the middle pad of the group of three to the left (in the photo) of the 36v marking. The photo's still not very clear. If you can see on the back side of the board that nothing is connected to that pad, then it makes it even more likely.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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Do you mean the cables outside the board?

Everything seem to be connected correctly.

Or do you mean to remove completely the board to check the circuit on the back?
 
D

Deleted member 4366

Guest
Do you mean the cables outside the board?

Everything seem to be connected correctly.
Or do you mean to remove completely the board to check the circuit on the back?
Yes. If it's not too difficult.
 
D

Deleted member 4366

Guest
I'm having another think about it and I'm not sure about the pad I mentioned before. I now think that it might be the one a bit further to the left between the two white arrows. Have a look at the back of that one as well.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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www.whatonlondon.co.uk
Just removed everything to take pictures.

Front:


Back:


It wasn't difficult at all to do that. Thanks for your help :)

Not sure what/where are the 2 white arrows?
 
D

Deleted member 4366

Guest
My new favourite is the one marked VD to the left of the slot, which was more or less hidden in the previous photo. It's still a bit hidden by a shadow. Could you take one more photo from another angle to show it clearly. Does the green wire reach it if you pull it a bit?
 

johnc461165

Esteemed Pedelecer
Aug 19, 2011
546
22
WN6
Can you take a close up photo of the corner where the wires are soldered rather than the whole board, also is there any sign of solder on the end of the green wire
 

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
My new favourite is the one marked VD to the left of the slot, which was more or less hidden in the previous photo. It's still a bit hidden by a shadow. Could you take one more photo from another angle to show it clearly. Does the green wire reach it if you pull it a bit?
Yes this one looks suspicious, on the back of the board the same pad looks like it has had a wire soldered flat across it...