MXR dead this morning... (and now alive!)

[Fog 25]

Hey Guys....I just figured out how to get double the range and instant charging while cutting 20 lbs off the bike....its great!

Fod. I told you to keep that Technology under wraps ⚡️now we are going to have to put out the video.

 

[Philip]

Here is the promised update.

Executive summary: After a lot of multimeter poking and part swapping between the bad bike and a good bike, the problem was tracked down to the BCU module. Replacing the BCU fixed it. The bike is finally fully alive and working well!

Here is how it went:

Dead electric bike... what do you do? Mostly poke things with a multimeter and swap components.

Replacing the key switch didn't help. Got to the 9V battery without removing the main battery. It was good, reading 9.14V.

We then processed with more parts swapping. Swapping displays didn't do anything. Even a missing display does not prevent a good bike from powering up, only from driving.

Then we proceeded with more visual inspection and multimeter poking. Apparently, @Mark911 knows every little wire in these bikes already. We first poked the key switch contacts and traced them down to the ACM (Accessory Control Module) connector under the front part of the seat. All the wires rang through but had no power in them.

According to @Rashid510, the problem was then down to either the ACM or the battery pack. Switching the battery packs between a bad and a good bike moved the problem onto the good bike. It's in the battery. Thanks to @snydes for the tips on how to remove the battery, I posted a little battery removal how-to here.

@Rashid510 was pretty sure that it was in the BCU (Battery Control Unit), which is built into the top cover of the battery pack.

Miraculously, the word had it that @ElectroBraap came across a spare battery top with a BCU in it. On top of that, he was willing to donate it to science, to the geeks who were going to dissect it and figure out how things work in the battery. Well... but here I came, the guy who needed it functional and not dissected. Awesome guy @ElectroBraap.

The battery top with the BCU came in the mail on Thursday.





I was afraid to take the battery apart, but I kept in mind that if I do not grab metallic things with both hands, I probably won't die.

@Mark911 gave me some battery disassembly tips. The top cover has a square rubber seal, so removing it was easy. But I could not remove it fully because the thick black/orange ground wire was holding the top cover down, not allowing me to pop it fully open. I had to remove the bottom cover too to free up more slack in that black/orange ground wire and then return back to the top cover.

The bottom cover has butyl instead of a rubber gasket. Mark recommended cutting through the butyl sealant with a razor blade. That didn't work for me, but carefully prying with a small flat screwdriver little-by-little eventually did the trick.

Mark also wrote a multi-page treatise on battery disassembly, so hopefully, he will post it here someday.

With my heart rate going through the roof, I took the bottom cover off, carefully pulled out the ground wire from the bottom module. The pic below shows the bottom of the battery with the ground wire out. I am holding the new top cover next to it.



The wire and other high-voltage contacts in the battery use these pin connectors.



I then flipped the battery back upright onto two 2x4 wooden boards under the battery case (not to apply pressure on the bottom module). The top cover came off easily.

The black/orange ground wire goes from the top of the battery to the bottom. It has connectors on both ends, and it cannot be removed easily. So I had to disconnect it from the old cover/BCU and reuse it. I removed the black/orange wire from the new BCU and connected the old wire to it. Popped the top cover back on and secured it with four bolts.

Flipped the battery upside down. Now, I had a dilemma whether to pop the ground wire back in. Something told me things might explode if I did. So I got a multimeter out and, indeed, measured 268 VDC between the two contacts that were supposed to be connected.



I thought... the voltage is high, but maybe there is not much current there. So, I took a regular household 110V light bulb, hooked it up between the two contacts, and nothing happened except for one tiny spark. No explosion. I then popped the ground wire back into the bottom module where it belonged. Done with the scary stuff.

The pick below shows the orange/black ground wire inserted into the bottom module and taped for safety.



EDIT: To re-seal the battery properly all you need is a properly sized butyl tape. The R-pack battery uses a butyl sealant on the bottom cover. The A-pack, apparently, uses it on the top cover as well. I lucked out and bought exactly what was needed the first time around -- CRL Sunroof Butyl Sealant Tape. It is about 9mm wide and 1.5mm thick, and long enough. One roll will probably let you seal a battery cover at least four times. /EDIT

As soon as I attached the battery to the bike, everything powered back on!

However, the display immediately lit up with a bright yellow warning light and showed me the dreaded Code 36. Damn it.

I thought this can't be real. One battery module can not have a dead BCU and Code 36 at the same time. @Rashid510 said that the new BCU may need a firmware flash. If it may need a flash, then it has memory, then it could store leftover information (including fault codes) from the battery packs on which it may have been installed before.

I needed to use MultiTool to diagnose the battery, update the BCU, and possibly clear the code. Many thanks to @416c7461 for the MultiTool software. Also, thanks to @TCMB371 for explaining how the heck to install it!

The installation of MultiTool took me two evenings, or twice as many hours as all the troubleshooting and battery work. I planned to use an Ubuntu bootable USB stick, which worked last month, but it didn't launch Ubuntu this week. So I had to follow the @TCMB371's method of installing an Oracle Virtual Machine. For some reason, my computer became ridiculously slow when I used this Oracle VM. This is why it took so long.

Fast forwarding, I hooked up MultiTool to the bike and checked the battery voltages. They all looked great, no reason at all for the new BCU to declare Code 36.



Cleared Fault Code 36. Done!



@Rashid510 confirmed that my current BCU firmware is the latest and greatest, so the BCU did not even need to be flashed. Here is my firmware configuration:



Many thanks to @ElectroBraap, @416c7461, @Mark911, @snydes, @OneLapper, @TCMB371, @Rashid510, and all the ex-Alta guys for their help and for having built such an awesome bike.

Also, having two identical bikes helped tremendously. Everyone -- go out immediately and buy yourself one more Alta!

 

[ElectroBraap]

Yesss! Great Success! Team work makes the dream work!

-electro

 

[TCMB371]

I just want to say, that's some next level brilliance regarding using the light bulb. I would have never thought of using that to test. I chuckled to myself after reading that. Just the image of you scrambling through your head and a light bulb goes off, and its a light bulb that's the idea hahahaha

 

[snydes]

If we keep putting our heads and resources together, we will keep these bikes running.

 

[Bloak]

Thanks for the write-up @Phillip.
Do we know if failure occurred at end of charge SOC 100%, or at end of balancing?
May have to wait for a dissect, but are there fuses within BCM ?

 

[Philip]

Thanks for the write-up @Phillip.
Do we know if failure occurred at end of charge SOC 100%, or at end of balancing?
May have to wait for a dissect, but are there fuses within BCM ?

It occurred at the end of charge, approximately. I interrupted the charge because I had to go to the track. Later, when I fixed everything, the bike sat for at least half an hour balancing itself.

I found only one obvious fuse there. It's the white thing in the middle of the first picture.

 

[Rashid510]

Good work Phillip! Glad to have been able to help out and keep the population alive (also not bzzaping yourself too )

 

[Fod]

So do you think the bcm would have failed if you kept it on charge till completely balanced? I don't want to cringe each time I stop charging before balancing has been completed.

 

[privateer703]

So does anyone think we should start attempting to get these circuit boards reverse engineered? I have a feeling this won't be the first time we have this issue.

 

[Bionicman]

That’s some serious sleuthing & mechanized electro work -kudos but agree we need a firm supply of BCUs

 

[OneLapper]

So does anyone think we should start attempting to get these circuit boards reverse engineered? I have a feeling this won't be the first time we have this issue.

In short, yes.

We are working towards that goal, either replication or finding a facility that can diagnose and repair any of the PCBs. What's slowing us up is lack of disposable inventory, lack of urgent need, and lack of disposable cash flow for R&D. Dumping time and money into a problem that doesn't exist, or doesn't exist yet, might not be the best use of resources. Up until a couple weeks ago we were not able to get our hands on much of the inner workings of an Alta. Most, if not all, new PCBs were acquired by ex Alta employees with the thoughts of keeping the employee owned Alta fleet running, and rightfully so. They have not come forward with much in the way of PCBs and battery components. I'm sure if we needed a specific item we'd be able to get one, like what happened for Philip, but it's a lot of behind the scenes effort to make that happen.

I'm my opinion, the most urgent issues we have are the Code 36 bikes out there that were diagnosed after Alta closed their doors, repairs that would have been fixed under warranty. Let's face it, an Alta without a good working battery sells for $2k. Yes, it can be parted out but no owner wants to take a $8-10k hit. It's possible that more battery faults will develop in the coming years. Personally, I think our time and resources, at this time, should be focused here. If we're lucky, a vendor like @AltaWest will eventually offer a complete battery solution for those owners that are not DIY'ers. Maybe they will offer lighter packs for MX racing, add on modules for ST and eudros, "get home" packs for the adventurers', (I've needed one of those a couple of times!). For those that do not want to buy packs, we hope to have DIY solutions.

The second most urgent issue, again, in my opinion, is the display. Now that @Rashid510 has access to the components, and two other members on this forum are currently developing their own display solutions, we have that problem covered and will have future options.

Faithfully submitted by OneLapper............

 

[Rashid510]

In short, yes.

We are working towards that goal, either replication or finding a facility that can diagnose and repair any of the PCBs. What's slowing us up is lack of disposable inventory, lack of urgent need, and lack of disposable cash flow for R&D. Dumping time and money into a problem that doesn't exist, or doesn't exist yet, might not be the best use of resources. Up until a couple weeks ago we were not able to get our hands on much of the inner workings of an Alta. Most, if not all, new PCBs were acquired by ex Alta employees with the thoughts of keeping the employee owned Alta fleet running, and rightfully so. They have not come forward with much in the way of PCBs and battery components. I'm sure if we needed a specific item we'd be able to get one, like what happened for Philip, but it's a lot of behind the scenes effort to make that happen.

The second most urgent issue, again, in my opinion, is the display. Now that @Rashid510 has access to the components, and two other members on this forum are currently developing their own display solutions, we have that problem covered and will have future options.

Faithfully submitted by OneLapper............

Most of us are willing to help and offer resources I won't speak for them, but we can do what we can. PCBs went all over the place. Can they be rebuilt? Sure, it requires us to negotiate/communicate with the fab houses that Alta used to build the PCBs here in the Bay Area. Or to move the fab to a different shop depending on component layout.

 

[privateer703]

I don't have a battery to offer, but I'd be willing to donate to further this endeavor.

 

[Fod]

Any way we can prevent what happened to Philip?

 

[Rashid510]

Any way we can prevent what happened to Philip?

Hard to say, could have been done by the charging procedure or a part of the charging process just going wonky.

 

[Fod]

Hard to say, could have been done by the charging procedure or a part of the charging process just going wonky.

Can you recommend a charging procedure?

 

[Rashid510]

Can you recommend a charging procedure?

Sure thing!

Bike off.
HV button off (red kill switch in Off position)
Plug bike in (110V for SM and charger connector on EX/MX)
Push reset button on GCFI
Turn key on (bike will at this point recognize charger connection)
switch HV enable on (red kill switch in On position)
Grab a beer.

 

[Philip]

Sure thing!

Bike off.
HV button off (red kill switch in Off position)
Plug bike in (110V for SM and charger connector on EX/MX)
Push reset button on GCFI
Turn key on (bike will at this point recognize charger connection)
switch HV enable on (red kill switch in On position)
Grab a beer.

If I did anything wrong, that would be the way I turned it off. Please write down the proper charger disconnect procedure.

 

[Rashid510]

Charging cycle should complete automatically/shut off at 100%. If you want to cancel the charging cycle before 100%, hit the kill switch to the Off position.