Bafang bbshd motor not working error code 08

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Finding my (electric) wheels
Sep 9, 2017
20
0
54
northumberland
i just got 20k from only one phase wire out of the three to the negative on the battery and that was it. no resistance to the wheel turning. the only time that i get a bit of resistance to the wheel is when. i keep my finger on the walk mode button and the wheel starts to make a bit of a clicking sound and you try to push the bike back words. then after about 6 seconds the error 8 comes on screen and the bike goes dead again.
 

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Finding my (electric) wheels
Sep 9, 2017
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54
northumberland
well i thought i would decide to take the wheel hub apart and have a look in side. well i wasn't expecting to see that someone has already replaced one of the hall censers. and not a very well done job at that as well. i will have a closer look at the one that has been replaced and see if it just needs re soldered/tied up etc. well hopefully that is all that is wrong with it. if not i am sure one of you lovey guys will help me test the censers to see if they are ok are have all gone bad.....5270752708527125271352714
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
4,181
2,077
Telford
That's interesting. It looks like you might have a few problems to solve.

1. To test the hall sensors, it's best to use the controller because sometimes they need a pull-up or pull-down resistor That's on the controller's pcb. Other times they have their own one either on the halls sensor pcb or included in the hall sensor package. Just connect it all up and switch on so that the 5v comes to the pcb, then you can test that the three signals switch on and off when you turn the motor. Sometimes one hall sensor is oriented different to the other two, so check that the 5v and ground tracks go to the right leg of the replaced one.

2. When a hall sensor goes and you give the motor full power, it's likely that a MOSFET in the controller will blow. Your measurements seem to indicate that's what's happened.

3. You should be able to feel the clutch working in the motor when you rotate the wheel backwards and forwards, so you need to get in in your hand and test that it's working. If you hold the middle, the outside should only rotate in one direction. It normally sits on a key in the axle, though some have a spline, so check also that it is actually fixed to the axle so that the centre doesn't rotate on it (key missing or broken).
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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West Sx RH
Indications are all three fets are faulty or at least two if only one showed 20k, on the Red side one should see infinity or a reading of one any zero reading is bad.
 

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Finding my (electric) wheels
Sep 9, 2017
20
0
54
northumberland
i tried retouching up the solder and sitting the censer better in place, but once all back together again the problem is still there. the new censer that has been put on is a 411F 132 the original ones i think are 63A 905
it was a bit difficult reading them as they must of had some sort of glue on them to keep them in place. is that new censer a ok match for the hub do you think.
how would i test the censers with a multi meter to see if they or good or bad..... thanks guys.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
4,181
2,077
Telford
i tried retouching up the solder and sitting the censer better in place, but once all back together again the problem is still there. the new censer that has been put on is a 411F 132 the original ones i think are 63A 905
it was a bit difficult reading them as they must of had some sort of glue on them to keep them in place. is that new censer a ok match for the hub do you think.
how would i test the censers with a multi meter to see if they or good or bad..... thanks guys.
Did you read my last post?
 

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Finding my (electric) wheels
Sep 9, 2017
20
0
54
northumberland
all the three censers are shaped like the small image that i have drew. plus they all face the same way out words.
in the second photo i have just noticed that there is a crack in the out green cable.5271652717
 

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Finding my (electric) wheels
Sep 9, 2017
20
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54
northumberland
i have been asking about on Ebay uk for just a new wheel only and up to now i have been offered one for £260
there is complete conversion kits which are Chinese sellers but are shipped from a warehouse here in the UK. they have much cheaper kits than what the uk guy i mentioned wants for just the wheel. but the Chinese sellers wont split the kits as they are not fully in control of the sale/warehouse. if you know what i mean.
i don't want to end up spending stupid money on the bike neither.
 

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Finding my (electric) wheels
Sep 9, 2017
20
0
54
northumberland
Hi again guys. the wheel is now sorted and working. there was a blue and yellow wire snapped in the main black cable going down to the small circuit board in the hub.
 
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