One will need to locate the white multi connector with ten , eleven or sometimes even twelve thin wires and disconect it ( the connector can be quite tight but will come away). One then needs to probe the wire out put of each pin out on the multi connector.

The easiest method I use to prevent accidentental shorting of pins and meter probes is to use a pair of arduino breadboard jumper wires (male to male).

Often the first wire is black on the multi connector and the last red, other wise the BMS should be marked B-/0 for the black one and B1 - B10 for the other ten positives.

 

If there are eleven thin sense wires on the connector follow the process below.

 

# Cell grp one.

Jumper wire one's end is pushed in to the first pin out B-/0 and the second jumper in to the the next pin B1+. Touch each jumper end with the meter probes to log the down the voltage reading (ones hopes it is 2.5v - 4.2v) with the meter dial set to DC 20v.

 

#Cell grp two.

Move both jumpers along one pin out . Move B1+ jumper into B2+ pin out and B-/0 into the vacated B1+ pin out, perform the same action for a voltage reading.

 

#Cell grp three.

Move both jumpers along one pin out again . Move B2+ jumper into B3+ pin out and B1+ in to the vactaed B2+ pin out , perform the same action for a voltage reading .

 

One needs ten seperate cell group voltage readings so one has to continue the same process seven more times .

 

Once done present the results to the forum here so we can see the readings.

The hardest part of the above is opening the battery.

No soldering or wire cutting or any other work is required at this stage bar collating ten voltage readings to ascertain any particular bad voltage imbalance.

Hi Neal

The maintenance man where i work had a look at battery,he said he was getting 41.6v on meter.Would this have been enough to get the pedal assist only had battery on charge around 7-8hours after green light and still not getting anything

Thanks

41.6v is good so if you are getting power to the display , going back to #1 and the intimittent PAS issue then one has to look at the PAS and bottom bracket to recheck all is well.

Importantly make sure the magnet disc is rock solid and firmly in place , it must only rotate when the cranks are turned . Sometimes they rotate or are not firm enough on the axle if that is where it is fitted, use your hand to manually check it . Also in it's rotation around the axis it needs to be fairly flat /even with a 1mm gap.

So since the last report of only having 39v , one has mangaed to balance charge the battery to a healthy 41.6v which is good.

Operationally the bike should work, if not then one has to look at the PAS or wiring.

Try walk assist the bike should work fine , depress the - /down pad and WA should activate.

Hi Neal

I will try those things suggested,you mention the pas and i was thinking about the 1mm gap.Have bought a crank remover to take a look at the internal workings of crank sensor and inner magnets to check if they have moved at all.

Thank you for all your help

Be very careful with a crank remover; make sure the inner bit is screwed all the way out so that the outer bit can screw all the way in to the crank. It's very easy to make a mistake, and if the outer is not fully screwed in you may strip the thread on the crank. I suggest to unscrew the inner at once after each use, so you don't make a mistake when you next come to use it in a hurry.

 

Excuse the 101 lecture, but its a mistake I have made, and many more experienced people as well.

Be very careful with a crank remover; make sure the inner bit is screwed all the way out so that the outer bit can screw all the way in to the crank. It's very easy to make a mistake, and if the outer is not fully screwed in you may strip the thread on the crank. I suggest to unscrew the inner at once after each use, so you don't make a mistake when you next come to use it in a hurry.

 

Excuse the 101 lecture, but its a mistake I have made, and many more experienced people as well.

 

Yes - been there and done that myself.

Be very careful with a crank remover; make sure the inner bit is screwed all the way out so that the outer bit can screw all the way in to the crank. It's very easy to make a mistake, and if the outer is not fully screwed in you may strip the thread on the crank. I suggest to unscrew the inner at once after each use, so you don't make a mistake when you next come to use it in a hurry.

 

Excuse the 101 lecture, but its a mistake I have made, and many more experienced people as well.

Salvation if it happens to you.

 

https://www.amazon.co.uk/gp/product/B00649NH42/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

So since the last report of only having 39v , one has mangaed to balance charge the battery to a healthy 41.6v which is good.

Operationally the bike should work, if not then one has to look at the PAS or wiring.

Try walk assist the bike should work fine , depress the - /down pad and WA should activate.

Hi Neal

Here are some photo's i've taken,just can't get head round why it won't work.Don't know what else to try that i haven't already tried.

Thanks

When all connected up , the display works yes ?

Yes Neal

Display works,just been out to try it on road.I can hear motor but have a second e-bike and although an older model bafang motor compared to suntour on problem bike it seems less of an effort getting up hills than what problem bike is.Have just put battery on charge again to try and get that balance on cells that you or someone else mentioned.Just wondering also about getting road tyreson it which i mainly ride on rather than the schwalbe nobby nics i have on now .

Thank you

Does the carrera have walk assist function ?

I don't think so,just as hi std and eco modes on display