Focus Aventura Impulse 2.0 - BMS/ Controller help

Hi all,

So I just snagged myself what I'm hoping was a good bargain. I got a used 2016 Focus Aventura Impulse 2.0 with no charger and a 'faulty' battery for $475 AUD.


The bike is nice enough just on it's own with decent brakes, group set and cheap but functional front suspension. Considering they what they were asking for it, I'm pretty happy with it.


Anyway, I checked the battery and total voltage was around 22V. Sure enough all cells were equally at 2.2V (it's a 10S pack). So I chucked it on a 2A 42V charger outside and brought it up slowly. No heat, or other charging issues so far...it's still charging now.

In order to charge I had to bypass the normal charge port/wires which go into the BMS as these would not accept a charge, and go direct to the cells main discharge leads.



However it still doesn't seem to want to interface with the bike, allow it to turn on, or give me any indication of charge state via the LED's.
I did a bunch of research and can't find much info out there. The closest I found was this troubleshooting guide:
http://newwheel.net/questions/pages/viewpage.action?pageId=5570561
But without an original charger I can't do much.

I also tried unplugging all connectors on the BMS to let it completely turn off, but that still didn't help. The charge connector has 4 pins with 3 wires and a resistor on it. I'm not sure what the 3rd, white wire does and I traced the resistor from the black (ground) back to the unused pin, so back to the charger....not sure why/what that does.


The bottom of the battery has 3 pins not associated with the main discharge leads. I'm assuming these are some sort of logic connection to the BMS for charge state. I tried hooking the charger directly to the main pos/neg terminals on the bike and managed to get it to turn on, however it would not display charge state and it would not power the motor.

So, does anyone have any suggestions on either how I can troubleshoot/reset the BMS, or how I can bypass it or the logic circuit in the bike?
I'm wondering if the BMS is toast, and how on earth I would find a replacement. I hate BMS...I never like to use them as they have caused me nothing but trouble.

Cheers

Well, I finally got the battery fully charged to 4.2V per cell, but still no luck bringing any of it to life unfortunately.
This is the BMS:



So I took the battery to a LBS today and they plugged it into a compatible charger for me to see if that would reset the BMS.

It caused one of the led lights to come on indicating low charge level (even though I had fully charged it prior). We left it on the charger for about half an hour, but when it was taken off all the LED's went off on the battery and pushing the button does nothing. Holding the button for a reset also didn't help.
So I'm thinking it's a faulty/toast BMS.

So I've just sent off about a dozen or so emails to every electric bike shop around Australia to see if they can order me a replacement BMS and charger, but I don't like my chances.

If that doesn't end up working then I have a choice to make. Pay the nearly $900 for a new battery and charger, or have a go at bypassing the BMS logic detection to get things running but risk frying the bikes controller in the process. If that happened I could always replace the controller, but then the built in display won't work, and I would have to buy and squeeze a new controller in there somewhere + a new CA, which is then adding up to 2/3 of the cost of just replacing the battery/charger.

Anyone got any suggestions?

Cheers

I thought I would update this thread with some news in the hope that it might help others in the same situation.

I ordered a compatible charger, which took a long time to arrive through a LBS, and cost just under $200AUD in the hope that I would be able to reset/recover the BMS somehow.
I had no idea the charger I ordered would also include a base station for charging off the bike, but I'm glad it did.



Initially I tried charging via the battery XLR type port, but found the same results as the LBS I took it to previously. No matter what reset procedure I followed, I could not get it to give me more than the one LED showing 0% charge, and it would still not power on the bike.
I then tried charging via the base station, and when I tried the reset procedure (hold button on battery for 8 sec) it worked and all the LEDs started flashing. I then left it on the base station for about an hour and when I next hit the button all LEDs lit up indicating full charge.


I took it for a 17km ride with my kid on the back (kids seat removed prior to this photo) and everything works well. The LEDs showed full charge still when I got back, but putting it back onto the base station charger showed it was charging from about 75%.


Unfortunately, I think there still is a problem with the BMS or something as the bikes display does not show the battery charge level and as mentioned the LEDs aren't showing charge state accurately.

(I found out holding down the "-" button resets the trip meter about 3/4 the way through my ride :lol: )

At least if I can charge it on the base station it should still work. It's just as well as for a new battery I was quoted $750-1000+. I must have reached out to at least 8 different LBS around Australia, but they all had the same response that they could not source me a replacement BMS and would only sell me a complete replacement battery. It's a sad state of affairs with modern consumer goods that they have to resort to potting all the electronics and preventing the public from buying individual parts to self repair broken goods.

Having only ever owned throttle based, hub motor E-bikes up till this point, and having started out my E-biking life with a Stealth Fighter, I do feel like this bike really makes one work before it gives it's full power. Maybe I'm less fit than I used to be (no I definitely am) but it feels like I really have to push hard to get full power from the motor on this thing.
Good thing I'm primarily keeping it as a backup bike and a bike for the wife to hopefully come to appreciate the electrons like I do.

All in all I can't really complain...I've spent a total of $665AUD for a bike that was selling as new 12 months ago for $3500.

Cheers

Hi,

Sorry for hijacking your post, but this is the only English info I can find in the web. The only info I have is the user manual. The LBS don't help because they don't sell that new model (I got it Imported) and don't have this service kit...

I have a newer version of Impulse system - Impulse Evo RS 2016 and even that it is only 400km old and that I strictly follow the manual - it stopped working today
After my arrival home by the bike, yesterday with 0km left, but not completely drained, I left the battery charging, and this morning I unplugged it (didn't check the state of the lights), mounted the battery and headed for work and bad surprise- the display showed 100% battery, but 0km range. Tried the assistance- nothing. Restarted the system- nothing, restarted the battery- same, factory reset the settings of the bike -no change. Checked the battery level via the battery LEDs- 0-17%(1LED flashing), although I charged it entire night, or at least I believe it was charging Checked the battery cycles left via the LEDs -showed 100%(all 5 LEDS on). Brought it back to the charger and plugged it and it started charging as if it is drained (1 led blinking). The charger showed charging state (1 green light flashing rapidly). That stayed 1 minute and then the battery charging light went out, but the charger's light stayed in charging state (flashing quickly). So I decided that same happened yesterday evening and during the entire night nothing was charged. I tried to put the battery in sleep mode to eventually reset the BMS- and wake it via the charger- I was able to do so according the manual, but nothing changed

Previously I had a BionX bike and I was tired of its closed system- I had so many issues and no LBS in my country, so I finally sold it to DIY ebike guy who was interested in repairing it for himself. Bionix had the battery shutting down after a day, so I decided to leave it and wait for the BMS to reset... with small hopes on that.

I am pretty frustrated now, because I buy a second expensive ebike and can get no support in my country. And there are no many options here, besides Importing. The Derby-Cycle guys (the manufactures ) are not of any help- they only send me a template that I should contact my local dealer. He, however, can only send it back to Germany, as he said that the only troubleshooting he could do is measuring the output voltage.He doesn't have this service kit and he doesn't have the same charger, either I, of course, want my bike working ASAP, as I use it every day, and don't want to pay the shipping fee of a 20kg bike plus hazardous fee for the battery...

So, I was looking for info in the web, but with no avail...even in German.

@Cowardlyduck does your original charger makes high- frequency noise when charging . I am asking because mine seems the same as yours with the only difference that it has the round magnetic plug (Rosenberger plug - ) and there is no option for a charging dock as the battery form-factor is different ( ). Mine is making this high-frequency noise since day 1 and I hope the charger is the problem, so I can only waste ~100$ for fixing the bike, but I also don't want to throw away an extra 100$ if something else is broken. I am already several thousand in...

What battery chemistry ?

At first sight, they look like Headways and should not be charged 4.2v
That could be the reason why your battery level indicator does not work properly.

kosio86 said:

@Cowardlyduck does your original charger makes high- frequency noise when charging . I am asking because mine seems the same as yours with the only difference that it has the round magnetic plug (Rosenberger plug - and there is no option for a charging dock as the battery form-factor is different. Mine is making this high-frequency noise since day 1 and I hope the charger is the problem, so I can only waste ~100$ for fixing the bike, but I also don't want to throw away an extra 100$ if something else is broken. I am already several thousand in...

Click to expand...

Hi Kosio86,

Yeah, looks like the same charger alright. Mine does not make a sound though, at least not that I've heard so if it does it's not loud.
That being said I do have several other chargers for various things that do make interesting noises. Some make high pitched noises when the charge is finished, just like you describe, others make clicking type noises, but in all cases they still work and charge the batteries they were intended for.
Do you have a base station charger like I posted above? That would be my first suggestion as that's what worked for me.
Apart from that, if your very careful you could try opening the battery, keeping the warranty stickers in-tact to check the BMS connections, and individual cell voltages. Only do that if your confident though since if you do have to send it back for repair they won't touch it if they think you've opened it.

MadRhino said:

What battery chemistry ?
At first sight, they look like Headways and should not be charged 4.2v
That could be the reason why your battery level indicator does not work properly.

Click to expand...

Nope.
They are Panasonic 18650B 3400mah cells. Definitely meant to go to 4.2V, and the 42V charger for 10 series links also indicates this.
Not the best C rate, but with 5 in parallel it's enough for a ~250W setup.

Cheers

@ kosio86
So today when my battery for the Focus was on the charger (base station) I just happened to be near it when it neared completion of the charge cycle.

It did in fact make that high pitched sound like you mentioned. It only lasted about a minute or so, then stopped. That's probably why I had never heard it before.
So there you go, even a brand new charger makes that sound...but only briefly when the charge is complete.
I've heard similar sounds from chargers before and I think it's the capacitors. When the resistance drops to a certain point the capacitors start making that kind of sound. I think it's normal.

Cheers

Thanks guys,

@Cowardlyduck- I don't think this model has a battery dock- at least mine came without and I haven't seen anywhere, neither in the user manual, nor in reviews, etc. My battery has two magnetic Rosenberger round female sockets- one for the output (the bike system) and one for charging and servicing. So, basically I could charge it while on the bike, or while taken off- both ways with the cable directly into the side socket.

Thankfully, I managed to deal with the problem. It appeared to be some kind of software bug, I believe. I visited the local dealer and he measured the battery voltage (I wasn't able to measure it directly on the battery charger pins, or the output pins as they are not active unless the BMS says so) and it was 42V - completely full. So we decided that the charger made that high pitch sound exactly because the battery was charged already. So, according to the dealer it was some calibration bug so that the BMS or bike were not recognizing the distance the bike could make, even though the bike was recognizing that the battery was 100% full. So, he offered that we should somehow fully discharge the battery and it should re-calibrate. Then I got my genius idea - to put the bike on a bike stand and tie the + button with a zip tie, so the walk assist (which was still working) could discharge safely the battery while it is still connected to the system. After ~20 minutes nothing did change, but after 40 minutes the battery indicator dropped to 90% and the distance indicator showed 46km on Ultra - and assistance started working again

It still would be better if Derby send a service cable to my local dealer (the only one in the country), so he could check the logs and eventually update the software, but I feel better now

I've been trying to make an adapter for a 42v charger I already have to work with the 4 pin XLR on a derby bike my friend has. I previously did the same thing (different voltage) for a juiced ebike.... which was simple (luckily juiced actually shows the pin out on their website, pin 1 positive, pin 4 negative). I tried that with this battery... no luck... then tried the inverse... no luck.

Do you guys know what the correct pinout is?... or is there something special needed beyond the 2 pins being connected?

progrock said:

Do you guys know what the correct pinout is?... or is there something special needed beyond the 2 pins being connected?

Click to expand...

I don't know the pinout sorry, but you are right about it doing something special.
The BMS definitely has issues in my battery and I regularly have to reset it by holding down the button while it sits on the charger.
Try playing around with the button while it's connected to a power source...you might be able to bring it back to life.

Cheers

Hey, if you have a functioning charger, please tell me you have a multimeter.... it would really help if I knew for sure which is positive, which is ground.

progrock said:

Hey, if you have a functioning charger, please tell me you have a multimeter.... it would really help if I knew for sure which is positive, which is ground.

Click to expand...

Ill try and find some time to have a look over the coming days.

Cheers

OK, thank you so much... trying to get this fixed for my friend... he's in the need of some cash pretty quickly (and while I loaded him some, and offered more, he's refusing to take more), so trying to help him sell some stuff he has, which in certain cases like this, requires getting some of his stuff into a functional state (as cheaply as possible). Needless to say, much easier to sell an ebike if it actually runs, and good to have a charger that'll work with it. Got a few other items to fix as well, trying to get it all ready for a swap meet he's planning to sell this Saturday and Sunday.

Any help is much appreciated, trying to do what I can without tearing this thing apart... but will do so if it comes down to that.

Hi progrock,

Here you go.
The first image is the base of the battery pinout.


I tested every pin and the only 2 with voltage across them are the ones shown.


There is no high voltage across any of the pins...I suspect it waits for a feedback signal from the BMS before it sends full votage. If the BMS does not send this signal you will not get any charge. A lot of chargers work this way....it's very annoying.

As per what was said earlier in this thread, I am unable to charge my battery using the cable and have to use the base unit. I suspect this is due to a BMS problem that the base unit must bypass.
You might want to consider buying a new charger that includes the base unit if you can't get it to charge.

Cheers

Thank you... and you are 100% correct... if only I had a clue what signal it's expecting on the 3rd wire. I tried throwing a few resistors across it (was hoping it was a 10k thermistor..... but no luck there). But, maybe the fact that you can get the charge to work off the base of it helps... I'm just not 100% sure what "C D R + -" labels stand for. I mean, obviously the "+" & "-" I know... but I assume that is out to the controller/motor... so not 100% sure which connections I want to try to throw power through to charge it (and def don't want to make things worse and fry this).

I'm trying to think of anything I can try before I go to my last resort.... replacing the BMS, requiring the whole batter pack. I really don't want to have to do that.... but if it comes down to that, I will.

Wait a second... that photo has your charger base unt on the ground, doesn't it?.... it looks liek it only has pins to the "+" "-" and "R" .... I'm praying thats "R" for recharge... then the + and - is for reading the voltage back.... sadly it could also be chargin via + anbd -, and require the same "signal" over the "R" that the main charge input wants, that I don't have.

progrock said:

Wait a second... that photo has your charger base unt on the ground, doesn't it?.... it looks liek it only has pins to the "+" "-" and "R" .... I'm praying thats "R" for recharge... then the + and - is for reading the voltage back.... sadly it could also be chargin via + anbd -, and require the same "signal" over the "R" that the main charge input wants, that I don't have.

Click to expand...

Yeah, your spot on.
I tried to get a replacement BMS and they won't do it. They will only let you ship a battery back to Focus for repair by which point you may as well just buy a new battery as the cost of shipping + repair is more than half the price of a new pack.
If you don't already have a charger with a base unit, that's what I would advise getting. It does seem like my pack has the same problem as yours in that it won't charge from the cable. However mine will charge from the base unit. From memory my replacement charger was about $140AUD.
The only other thing I did do was open my pack up and charge it directly to the battery contacts before I bought the new charger, but even doing that would not let me reset the BMS and let it power the bike.
I still have to periodically reset the battery by holding the button with it on the charger or it won't turn on the bike, but apart from that it works fine.

Hope that helps your situation.

Cheers

You basically described my plans for a last ditch effort before replacing the BMS. Gonna charge the battery manually (debating on just charging directly across the battery, or actually going through the effort to wire up a balancing charger... I do have a 10s charger... but probably not necessary)... just wanted to see if maybe getting the battery up from completely dead may help me get this charger to work.

Since I'm helping a friend, who's trying to spend as little money as possible, I just bough a <$20 charger, and a $5 XLR 4 pin connector... and made a 3 pin to 4 pin adapter. Was hoping that's all I needed, but obviously not. Just trying to think of any thing else I can try to do before I just rewire a new BMS in.... which I don't really want to do, considering I'm not 100% sure what the 3 other connections are to the bike, and for all I know the bike won't even work if I just have a standard BMS in there... though I it would. Of course it's a German bike (don't get me wrong, I am a HUGE fan of German cars)... they do love to over-engineer things.

Thanks for the help, hopefully I get this figured out soon enough... this has been keeping me from finishing my own ebike build.

Bob

Hello,

I just received an Impulse battery and I think it has a BMS problem. It is a pity I cannot see the images of the voltages of the previous post from the charger (I do not have a charger to charge the battery)

Could someone with a multimeter measure the voltage between - and R in the dock charger please? (between the pins of both sides)
Dock:
https://cdn.shopify.com/s/files/1/0139/1925/6622/products/impulse-acculader_1_700x700.jpg?v=1573732887

Battery connections:
https://hollandbikeshop.com/img/prod/impulse-battery-36v-17-5-ah-397206-2-l.jpg

I think it has something similar than the bosch chargers, they need a wakeup signal to the bms to get charged or to deliver the 36V
https://www.pedelecforum.de/forum/index.php?threads/bosch-diy-charger.59667/

Thanks!

Cowardlyduck said:

Well, I finally got the battery fully charged to 4.2V per cell, but still no luck bringing any of it to life unfortunately.
This is the BMS:

So I took the battery to a LBS today and they plugged it into a compatible charger for me to see if that would reset the BMS.

It caused one of the led lights to come on indicating low charge level (even though I had fully charged it prior). We left it on the charger for about half an hour, but when it was taken off all the LED's went off on the battery and pushing the button does nothing. Holding the button for a reset also didn't help.
So I'm thinking it's a faulty/toast BMS.

So I've just sent off about a dozen or so emails to every electric bike shop around Australia to see if they can order me a replacement BMS and charger, but I don't like my chances.

If that doesn't end up working then I have a choice to make. Pay the nearly $900 for a new battery and charger, or have a go at bypassing the BMS logic detection to get things running but risk frying the bikes controller in the process. If that happened I could always replace the controller, but then the built in display won't work, and I would have to buy and squeeze a new controller in there somewhere + a new CA, which is then adding up to 2/3 of the cost of just replacing the battery/charger.

Anyone got any suggestions?

Cheers

Click to expand...

I know it is 7 years late, but I work as a local battery repairman here, dealing with about 30 impulse batteries/ month. The one led means the bms is "uncalibrated", i deal with this by using a calibration machine. The ATGF1500, it's quite expensive at 900 euros for the machine it self, but for those local, I charge 25 euros for a recalibration

andreaskhoi said:

I know it is 7 years late, but I work as a local battery repairman here, dealing with about 30 impulse batteries/ month. The one led means the bms is "uncalibrated", i deal with this by using a calibration machine. The ATGF1500, it's quite expensive at 900 euros for the machine it self, but for those local, I charge 25 euros for a recalibration

Click to expand...

Thanks! It's never too late for input!

This bike/battery is still going strong after all this time. It still needs the occasional reset via the button while on the base charger, but it still works well. I put some nobby tires on it and take it off-roading on MTB trails even and it works great.

So if mine still works after pressing the button to reset it do you know if that means my BMS is actually working ok?


Cheers

andreaskhoi said:

dealing with about 30 impulse batteries/ month

Click to expand...

Hello Andreas, kindly asking for your advise as you are experienced with Impulse batteries.
I have an Impulse Evo RS system, where the BMS does not engage the main battery switch (the six P-MOSFETs) for some reason. All other functions, aux 12V power, CAN communication to the display/motor seem to be working fine. If I bypass the main switch, or use a bench supply instead of the battery, the motor works (at least in walk assist mode).
My suspicion is the BMS does not receive some CAN command from the display (or the motor) because of some software version difference between BMS and motor/display. Can this be true, or should I look for e.g. P-FET driver malfunction?
Thank you!

dlwest said:

Hello Andreas, kindly asking for your advise as you are experienced with Impulse batteries.
I have an Impulse Evo RS system, where the BMS does not engage the main battery switch (the six P-MOSFETs) for some reason. All other functions, aux 12V power, CAN communication to the display/motor seem to be working fine. If I bypass the main switch, or use a bench supply instead of the battery, the motor works (at least in walk assist mode).
My suspicion is the BMS does not receive some CAN command from the display (or the motor) because of some software version difference between BMS and motor/display. Can this be true, or should I look for e.g. P-FET driver malfunction?
Thank you!

Click to expand...

I haven't tested anything but bafang with 36v, no com. But if it works with just plain 36v, you could just hook up a generic bms.

S

Cowardlyduck said:

Thanks! It's never too late for input!

This bike/battery is still going strong after all this time. It still needs the occasional reset via the button while on the base charger, but it still works well. I put some nobby tires on it and take it off-roading on MTB trails even and it works great.

So if mine still works after pressing the button to reset it do you know if that means my BMS is actually working ok?


Cheers

Click to expand...

Should be, not a engineer behind impulse, but from my dealing with impulse batteries, that should be fine.