Help! Voilamart 26” front hub looking for repair

vfr400

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Ok IM GETTING CONTINUITY FROM ALL 5 wires on PCB . What next?
There’s the 3 thicker wires Green yellow and blue in the motor end that run through the same cable . I’ve found their contacts at controller end I’ll try to make a contact at motor end and test but I think they’re unlikely cos they’re thicker sturdier and if the thin PCB wires survived in sure they will have too
Hold on, try testing it like this:
Put your black probe on one of the 6 pads on the pcb (H, 5v,GND, A, B, C.), then put your red probe on each of the 8 or 9 pins at the other end of the cable to determine how many beep. repeat for the other 5 positions. If more than one beeps for any one pad, you're out.

Basically, it's impossible to do any damage to the hall sensors or the resistors/capacitors without the cable being damaged. If your motor was OK before the incident and didn't work afterwards, conductors in that cable must have touched. there's no other way to get a problem.
 

mikeconnect

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Jul 3, 2020
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Hold on, try testing it like this:
Put your black probe on one of the 6 pads on the pcb (H, 5v,GND, A, B, C.), then put your red probe on each of the 8 or 9 pins at the other end of the cable to determine how many beep. repeat for the other 5 positions. If more than one beeps for any one pad, you're out.

Basically, it's impossible to do any damage to the hall sensors or the resistors/capacitors without the cable being damaged. If your motor was OK before the incident and didn't work afterwards, conductors in that cable must have touched. there's no other way to get a problem.
Gotcha. So I’ve only tested for a break and not a short . Not there at minute I’ll check it later thanks
 

WheezyRider

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Apr 20, 2020
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Ok IM GETTING CONTINUITY FROM ALL 5 wires on PCB . What next?
There’s the 3 thicker wires Green yellow and blue in the motor end that run through the same cable . I’ve found their contacts at controller end I’ll try to make a contact at motor end and test but I think they’re unlikely cos they’re thicker sturdier and if the thin PCB wires survived in sure they will have too
Not necessarily. The small wires can slip around more than the thicker wires and it's the insulation on the thicker wires that is the most vulnerable thing, if that gets cut and you have a short, it can mess things up very quickly. You need to make sure the motor power wires have continuity and not assume they are ok.
 

vfr400

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You can test the motor wires from the controller end. Each one should beep to the other two. You can then test from each to the 5 hall wires. If any beep, you're out.
 

WheezyRider

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I asked that question to Wheezyrider for my own knowledge. Later, you started to test that on his behalf, so I encouraged you to complete the test.

I'm losing track of where we are with all this... o_O

Ok, the top of "R1" is connected to +5v. The bottom of "R1" is connected to ground. The top of "R2" is connected to ground, the bottom of "R2" is connected to pad "H" which seems to be the speed limit indicator, which Mike doesn't have on his.

In terms of "top" I mean the outside of the motor, so the text is the right way up.
 

WheezyRider

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By the way R1 which had not been replaced shows 328 ohm . I assume I’m doing it correctly . The 200 ohm setting stayed on 1 and the 2000 showed 328. Does this mean that R2 needs a resistor of same value ??
That sounds different, if I put the multimeter across R1 I get several hundred kilo Ohms
 

vfr400

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By deduction, R1 is a capacitor to filter high frequency noise out of the system. R2 is either a pull-down resistor that makes the speed sensor work properly when fitted or its another capacitor to filter noise from it. Either way, without the speed sensor, it doesn't do anything. likewise, the other capacitor is so small that its function wouldn't be missed if it wasn't there.
 

WheezyRider

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Am I mistaken or are these circuits circled in yellow broken ? after the crazy guy did his terrible soldering on sensors I’m thinking this PCB is a write off after that guy got his hands in it . I’ll take advice on that and persist if you think it’s worth itView attachment 37411

It's messy, but not necessarily unusable.

Broken tracks can be repaired with a blob of solder in the right place, missing tracks can be replaced with bridging wire.
 

WheezyRider

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By deduction, R1 is a capacitor to filter high frequency noise out of the system. R2 is either a pull-down resistor that makes the speed sensor work properly when fitted or its another capacitor to filter noise from it. Either way, without the speed sensor, it doesn't do anything. likewise, the other capacitor is so small that its function wouldn't be missed if it wasn't there.
I think you are right about "R1" and I think "R2" is still a capacitor, but in Mike's case it's redundant anyway.

But I still think it's not worth splashing out on a new PCB that may not fit, or if it comes with hall sensors, there is no guarantee they are the right ones for the job. Mike's probably better off repairing the PCB he has.

I don't want to be an Eeyore on this, but I have wasted a fair bit of money over the years buying parts off of eBay etc that look like they might do the job, but then finding out that they don't.
 

WheezyRider

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He might have another path through his hall sensors.
Maybe, but I couldn't find anything with a resistance that low on mine and I'm wondering how likely is it that the layout is that different (other than no limiter included)? Could it be the modifications made by the "friend" have caused this low reading?
 

vfr400

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Maybe, but I couldn't find anything with a resistance that low on mine and I'm wondering how likely is it that the layout is that different (other than no limiter included)? Could it be the modifications made by the "friend" have caused this low reading?
The soldering is messy and he has the wrong type of hall sensors. Anything is possible.

SS49s consume about 6 ma x 3 = 18ma. At 5V, that would make their combined resistance about 278 ohms, which is not far off what you measured.
 
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mikeconnect

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Jul 3, 2020
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The soldering is messy and he has the wrong type of hall sensors. Anything is possible.

SS49s consume about 6 ma x 3 = 18ma. At 5V, that would make their combined resistance about 278 ohms, which is not far off what you measured.
Once I can get back to the 3 thick wires and Test and eliminate them I’d prefer to find another board cos I posted a photo which nobody has commented on where it looks like the actual circuits have been broken by the crap soldering . Please look at that photo cus waste yo talk about what new components it needs if the circuits are goosed
 

mikeconnect

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I think you are right about "R1" and I think "R2" is still a capacitor, but in Mike's case it's redundant anyway.

But I still think it's not worth splashing out on a new PCB that may not fit, or if it comes with hall sensors, there is no guarantee they are the right ones for the job. Mike's probably better off repairing the PCB he has.

I don't want to be an Eeyore on this, but I have wasted a fair bit of money over the years buying parts off of eBay etc that look like they might do the job, but then finding out that they don't.
Look at the photo I posted of the board nobody has commented on it. I pointed out 2 yellow circles where it looks like the bad soldering fiend damaged the actual circuits. Am I right Or not? cos if so it’s a new board . Anyway I’m still to Beep check the last 3 thick wires
 

mikeconnect

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Jul 3, 2020
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I think you are right about "R1" and I think "R2" is still a capacitor, but in Mike's case it's redundant anyway.

But I still think it's not worth splashing out on a new PCB that may not fit, or if it comes with hall sensors, there is no guarantee they are the right ones for the job. Mike's probably better off repairing the PCB he has.

I don't want to be an Eeyore on this, but I have wasted a fair bit of money over the years buying parts off of eBay etc that look like they might do the job, but then finding out that they don't.
R2 is a capacitor because dickhead fitted one without knowing what the original was
 

mikeconnect

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Jul 3, 2020
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Maybe, but I couldn't find anything with a resistance that low on mine and I'm wondering how likely is it that the layout is that different (other than no limiter included)? Could it be the modifications made by the "friend" have caused this low reading?
Whoops sorry you did reply to this photo
Maybe, but I couldn't find anything with a resistance that low on mine and I'm wondering how likely is it that the layout is that different (other than no limiter included)? Could it be the modifications made by the "friend" have caused this low reading?
ok that’s it !! All 8 wires have passed continuity and short test. Next please
 

mikeconnect

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Jul 3, 2020
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Wires eliminated . I’m prepared to take on the PCB solder challenge cos nobody knows where to get replacement board that they’re sure of. So ss41?for sensors ? Then Only prob is R1 and R2 . To remind you R1 is the original whatever it is . But R2 is capacitor replaced by clever boy who was only guessing