ezee torq fault, starts up, odd gauge display, then dies

[Nealh]

That looks better though battery isn't very well balanced, cell #5 (Green) is the worst cell out of balance and may be the cause of your problems.
Br 4.11v.
R 4.11v.
Or 4.11v.
Y 4.11v.
Gr 4.06v.
Blu 4.1v.
Pur 4.2v.
Gr 4.1v.
Wh 4.2v.
R 4.2v.

It is possible (Green) it may be a bit weak and voltage may or may not collapse.
For now it will not charge any more as 3 cells are already at 4.2v so bms will not allow charger to switch on.
Ideally you need to use the bike ( if the system allows ) and deplete the battery voltage and retest cell levels before attempting a charge to see if there is an errant run away cell collapsing.
Equally you can discharge the battery via the main discharge circuit using 3 x 12v lights car lights wired in series to put a load on the battery, with your meter also wired up you should see any voltages crashing form the cell groups.
What ever you do test cells before any charging and post results.

Do any of the cells look puffy or swollen ?

 

[brettule]

The bike motor won't run for any longer than 3 seconds at a time, I can turn on the system though and the tail light illuminates so I can use that to drain the battery. How far should I drain? All the way until the battery is completely flat?

 

[Woosh]

have you got a 12V 50W halogen light bulb?
Use it to drain the cells that are high until they reach about 3.6V
Then hopefully the battery can be charged up again, then leave it to rebalance over night.

 

[Nealh]

Although battery is unbalanced we don't know if any of the cells are collapsing when a load is applied, you need to apply a load to discharge and check the cell voltages during the discharge to see what they are doing.
If all looks fine then the controller may be the next to fault find.

 

[brettule]

She's been trickle discharging for a few days. The display will temporarily show 3 out of the 5 bars for charge if I tap it. Latest readings are:

Total: 36.9v

Brown     3.68v
Red    7.36v
Orange    11.05v
Yellow    14.74v
Green    18.43v
Blue    22.1v
Purple    25.8v
Grey    29.5v
White    33.2v
Red    36.9v

How far should I drain the battery, all the way until it's totally flat?

 

[Nealh]

Those values look pretty well match give or take 0.01 or 0.02v's. Put it on charge and when charger say's it's done leave to balance a couple of hrs longer, then check voltages again.
However you will not know if it all holds up until a proper load is placed upon it and voltage's re-checked, all can be a bit time consuming with batteries and finding any fault.

 

[brettule]

That Nealh, I ran the drain for a little longer over the weekend and took a final set of readings:

Total: 35.0v

Brown     3.49v
Red    7.00v
Orange    10.49v
Yellow    14.01v
Green    17.52v
Blue    21.0v
Purple    24.5v
Grey    28.0v
White    31.6v
Red    35.0v

I've put it on charge now and will leave it overnight. I'll recheck the values tomorrow then plug the battery back in and let you know if the bike kicks back into life. Fingers crossed.

 

[Nealh]

Taking it lower again quite good on trickle discharge last two cells a bit different.
Wh 3.6v.
Red 3.4v.
All others 3.48 - 3.52v

It is what happens on a proper discharge load that we will know how well it is behaving.

Quite often a slow discharging battery behaves well but as mentioned given a more serious load and it can behave quite differently if a cell is weak.
What you do need is real time voltage readout during discharge/load applied to how voltage behaves and whether it sags badly or crash's, depending on the read out a cause may be seen or the cut out fault may lie elsewhere with loose /broken wire or even a wire shorting.

 

[brettule]

I charged it overnight, tested it on the bike and it's the same fault symptom as my first post. Readings are

Total: 41.3v

Brown     4.10v
Red    8.20v
Orange    12.31v
Yellow    16.42v
Green    20.5v
Blue    24.6v
Purple    28.8v
Grey    32.9v
White    37.1v
Red    41.3v

What's the conclusion?

 

[Nealh]

Your still at 41.3v, battery is a bit weak and unbalanced still.
Weakest cell is 4.08v so either the voltage is collapsing big time or a fault elsewhere.
4.1v
4.1v.
4.11v.
4.11v.
4.08v.
4.1v.
4.2v.
4.1v
4.2v.
4.2v.
Wire up a volt meter and see what happens to the voltage reading when you apply throttle or pas.
Until we know what happens with the voltage when a load is applied we can't really go any further, if the battery has had it then there is only one solution.
If you had another good battery to try and the same happened then we would know battery isn't at fault.

I did have a similar issue once like yours with a healthy battery, power only lasted a couple of secs even with another battery that was also good. The controller was at fault and the lvc kept cutting in.

 

[brettule]

Thanks Neilh. Here are the latest findings.

41.3v when she's idle, then I throttle it up and get an initial voltage drop to 40.1v, then she settles at 40.9v for 2 or 3 seconds before the bike dies and the voltage returns to 41.3v

Took a video of the readings here

If we're thinking it's a battery, are they expensive? What's the best way to go about buying them and what sort?

 

[Nealh]

1.2v sag generally doesn't suggest much is wrong over the whole battery but if it is occurring with just one cell then instant cut out as you are seeing is the lvc doing it's job.

Testing and checking for a fault is time consuming but in the end cheaper then swapping out components for the sake of trying to find an answer.

Most likely it is the battery, though a few more checks are needed.
The next check is to try and check each individual cell voltage whilst under load, any one cell that loses 1.2v will be the cause and lvc will come in to play.
Check the 4.08v cell firstly, if it lost the full 1.2v then it would collapse to 2.88v and is knackered the same applies to any other cell any one could be hitting 2.9 - 3v.

 

[brettule]

Did a load test on each cell. This is the reading just before the lvc kicks in and cuts the bike. What does this tell you?

Brown     4.01v = 4.0v
Red         8.0v = 4.0v
Orange   12.1v = 4.1v
Yellow     16.1v = 4.0v
Green     20.3v = 4.2v
Blue        24.4v = 4.1v
Purple     28.5v = 4.1v
Grey       32.6v = 4.1v
White      36.7v = 4.1v
Red         40.9v = 4.2v

 

[Nealh]

Those values look very good, did you charge the battery up again as the Green which was under 4.1v now shows 4.2v and no voltage sag also red shows no voltage sag both at 4.2v. It could be there is a fault on the bms discharge side which is impossible to fault find unless there is a bad wire contact/wire break or solder connection which may cause a bottle neck for amp/voltage flow and cause shut down. There does appear to be an anomaly, other wise the battery readings so far suggest it is still pretty good and voltage is holding up well.

The only way to rule out a battery fault is if you had another one to try or borrow one to try from a friend, other wise we will have to fault find the whole system to confirm that the battery may well be at fault.

Fault finding for a battery wire issue is easy if your meter has the continuity/buzz alarm function, set the dial to this function and probe the very end of each wire/contact to indicate no wire breaks or poor solder contact.

If the battery isnt't at fault then the issue will lie elsewhere with an issue of conflict or a fault, so fault finding needs to be checked on wiring and components.

Ruling out any throttle or pas issue is simple, disconnect the throttle. Power up on pas only and see if it cuts out. Also disconnect any brake sensors.
If no joy reverse the role and disconnect pas and try throttle only.

 

[Nealh]

Trying to fault find and explaining what to do is much harder then physically carrying out the check which I could do all within a couple of hours.

All that can be done is to try component testing with a good bit of patience to try and find an issue, aside from trying another battery. The battery as mentioned does appear to be holding voltage up.

So far it appears your patience isn't wearing thin from your cool replies so you will just have to be methodical to try and track the down the issue.