2013 Zero XU Battery Problem, Possibly More. Seeking Help

robby

10 mW
Joined
Oct 12, 2015
Messages
32
Location
Andover, MA
Hi folks,

I have a 2013 XU that won't turn on. Worked fine a week ago and battery had been charged since then.

When I try to turn it on, I do not see anything on the display, no backlight, nothing.

When I plug it in, the green charge LED does not illuminate. I do hear a brief click (I presume from the charger relay). I do not see any action on the battery BMS LEDs.

All fuses (4 main and 5 high voltage) check out.

I detect voltage at the Gen4/DC converter (orange cables, 4 connection points on top) while it is plugged in. It starts low and ramps to at least ~40V (I'll keep checking to see how high it gets).

Any ideas on what my problem might be or what more I can do to troubleshoot?
 
I would check the wiring first, if you can't find any loose connectors. Doesn't the bike have a DC contactor/relay? check if it switching/seized or if it is getting power at all. the next thing I would do is to check the wiring Diagramm of the controller and start measuring the voltages.
 
eee291 said:
I would check the wiring first, if you can't find any loose connectors. Doesn't the bike have a DC contactor/relay? check if it switching/seized or if it is getting power at all. the next thing I would do is to check the wiring Diagramm of the controller and start measuring the voltages.

Thanks. I can't find any loose connectors. Double checked all fuses, verified ignition and kill switch are open/closed in their proper positions. My understanding is there is a contactor/relay in each battery but I don't hear it clicking and I don't know how to manually verify it. BMS LEDs aren't on, and a BMS reset doesn't do anything.

Interestingly, I find that no +12V is being supplied from the DC-DC. When I supply it from a separate power supply, I get lights, signals, and horn, but still no instrument cluster. No backlight, nothing. Does that mean my IC is faulty? I can trace the wires if nobody knows, it's just slow because I don't have any schematic and there are lots of wire clips and cable tethers.

I'm hoping to bring my battery to a dealer who can check the BMS, but the local folks are telling me they have no tooling to look at '13 battery packs.

Anything else I should check with the voltmeter or any other ideas?
 
Well the reason for the 12v converter to be unpowered is because the battery isn't supplying juice to it.

Now I can only think of two things:

Either the battery has a fault (wouldn't blame it for it's age)
Or your key switch is broken entirely (Less likely in my Opinion, but you can switch the wires manually if you dare fiddle around)

Also the Controller should have two thick wires on the input, check the wires if it's getting main power, to see if it would just need to be switched on.
 
eee291 said:
Well the reason for the 12v converter to be unpowered is because the battery isn't supplying juice to it.

Now I can only think of two things:

Either the battery has a fault (wouldn't blame it for it's age)
Or your key switch is broken entirely (Less likely in my Opinion, but you can switch the wires manually if you dare fiddle around)

Also the Controller should have two thick wires on the input, check the wires if it's getting main power, to see if it would just need to be switched on.

The ignition is definitely fine. I tested continuity.

It sounds like both batteries have a fault. This is frustrating as they are only 2.5 years old (despite the model year, they were bought new in 2015 from the factory). Also concerning that they'd both die so quickly together, which is why I worry about a problem elsewhere.

The instrument cluster does not have any thick wires. There is a red one on the harness that I tried sending +12V into but it did not illuminate.
 
Could you post some pics where the battery connects?

also when turning the ignition, check if there is a voltage on the main battery terminals (I'm talking about the really thick wires)
 
eee291 said:
Could you post some pics where the battery connects?

also when turning the ignition, check if there is a voltage on the main battery terminals (I'm talking about the really thick wires)

Sure, photos here: https://photos.freerobby.com/Projects/Zero-XU/
(#5 and #6 have a battery and contact)

Turning the ignition does not create voltage anywhere that I can detect. When the bike is plugged in (regardless of ignition state), there is about 40V on the battery terminals. As soon as I unplug it, the voltage begins dropping, albeit slowly, down to 0. Is this evidence that the contacts are closed in the batteries, or are there caps somewhere on the bike that are holding a charge?
 
Can you also measure 40V on the controller terminals? I'm guesssing the Capacitors in the Controller usually hold a charge.

Also what's up with the 40V? If the battery isn't charging shouldn't the charger float somewhere closer to 60v? 40V is below the BMS cutoff.
I think you should investigate on the charger side also.
 
eee291 said:
Can you also measure 40V on the controller terminals? I'm guesssing the Capacitors in the Controller usually hold a charge.

Also what's up with the 40V? If the battery isn't charging shouldn't the charger float somewhere closer to 60v? 40V is below the BMS cutoff.
I think you should investigate on the charger side also.

Yeah, the 40V measurement is at the controller B+/- terminals. Good point about caps in the controller.

I agree 40V raises more questions than it answers. I wasn't sure if that was indicative of a bad charger, or if the battery is bad and so the CCU is being cautious in what it sends. If 40V isn't enough to trigger the BMS that sounds like a charger problem. But then how did my batteries wind up completely dead within a week? Can you think of a situation where a defective charger would cause them to drain?

My next step is to measure the output voltage of the charger itself, rather than after the CCU. Unfortunately that is a disassembly nightmare, but on the bright side if the problem is the charger, that is probably the cheapest and most available part to replace on the entire bike. But I suspect I may still yet have dead batteries, as I cannot explain the total lack of power through the charger alone.
 
I don't know if this is true on the 2013 model, but on the older ones the battery would self-discharge within a week.
 
Update: both batteries are deep discharged... 15.7 and 18.8 volts. Zero tells me there is no salvaging the cells. Cost of replacing them and the chargers is 3x what I paid for the bike new in 2015. I'm so bummed. Will investigate how much it'd cost to rebuild the battery packs but I'll likely be parting it out in a few weeks. If anybody needs any XU parts, let me know.
 
robby said:
Update: both batteries are deep discharged... 15.7 and 18.8 volts. Zero tells me there is no salvaging the cells. Cost of replacing them and the chargers is 3x what I paid for the bike new in 2015. I'm so bummed. Will investigate how much it'd cost to rebuild the battery packs but I'll likely be parting it out in a few weeks. If anybody needs any XU parts, let me know.

Sad to hear.

If you are up for it, there are a few guys who replaced their cells with Nissan Leaf cells.
 
robby said:
Update: both batteries are deep discharged... 15.7 and 18.8 volts. Zero tells me there is no salvaging the cells.

I'm not so sure about that. There may be a way to revive the cells if they were not reversed during discharge. When cells get below a certain level, normal charging current can permanently damage them. A very low charging current (maybe C/100) is needed to bring them up to the safe level, then the current can be increased. I've used many cells that have been brought back from zero volts and they seem to perform normally.

The BMS is likely inhibiting charge at this point, so the only way is to take the pack apart and get access to the actual cell connections. It's possible the pack is potted in a way that makes this impossible.

If this is the case, it may be possible to put the low current charge into the main discharge wires going to the controller.

Since your other options involve replacing the cells, there isn't much risk in attempting reviving the cells (other than increased fire risk).
Charge in a fire-safe location.
 
thoroughbred said:
Yes bummer. I'd be interested in the whole thing or parts depending on your location if you decide to move on.

I'm in northern MA. Happy to part out what's left (blinkers and foot pegs? lol) if I wind up scrapping it.

eee291 said:
Sad to hear.

If you are up for it, there are a few guys who replaced their cells with Nissan Leaf cells.

I'm considering this. I don't even know if my BMS are any good though, and I would hate to rebuild the battery packs only to have yet another proprietary parts project on my hands. Are the Leaf cells the same voltage spec as the originals, and if not will the BMS monitor them properly?

I suppose I could work around these issues with an offboard charger.

fechter said:
I'm not so sure about that. There may be a way to revive the cells if they were not reversed during discharge. When cells get below a certain level, normal charging current can permanently damage them. A very low charging current (maybe C/100) is needed to bring them up to the safe level, then the current can be increased. I've used many cells that have been brought back from zero volts and they seem to perform normally.

The BMS is likely inhibiting charge at this point, so the only way is to take the pack apart and get access to the actual cell connections. It's possible the pack is potted in a way that makes this impossible.

If this is the case, it may be possible to put the low current charge into the main discharge wires going to the controller.

Since your other options involve replacing the cells, there isn't much risk in attempting reviving the cells (other than increased fire risk).
Charge in a fire-safe location.

Whoa, interesting. I had no idea. Zero sent me a diagram (see attached) indicating how to read the actual pack voltage (I wasn't using the main contacts). Do you think charging would be blocked at those pin locations as well? Regardless, I have little to lose by opening the battery and giving it a shot.

So for C/100 of a 2.8 kWh pack, you'd recommend e.g. 116V DC @ 241mA, yes? Any charger or power supply you'd recommend for this? (The bench supply I have access to tops out at 60V).

View attachment Battery Flowchart Rev01.pdf
 
Why the heck do you need 116V DC?

Isn't 48v enough?

even if it isn't, I would try to get the cells to at least 48V before you buy yourself another power supply.
 
robby said:
Whoa, interesting. I had no idea. Zero sent me a diagram (see attached) indicating how to read the actual pack voltage (I wasn't using the main contacts). Do you think charging would be blocked at those pin locations as well? Regardless, I have little to lose by opening the battery and giving it a shot.

So for C/100 of a 2.8 kWh pack, you'd recommend e.g. 116V DC @ 241mA, yes? Any charger or power supply you'd recommend for this? (The bench supply I have access to tops out at 60V).

Battery Flowchart Rev01.pdf

Well, that's higher than any of my batteries, so I don't have anything that goes that high. The current sounds OK. Even 500mA would probably be OK to bring them up.

If you can measure the voltage on the pins, then it means you can charge through them. If you can access sections of the pack through the connector, then maybe you can find chunks that are under 60v and you can use your bench supply.

Another trick I've used before is to place another power supply in series with my bench supply to get more voltage. To do this you need to put a big diode across the output of the bench supply to make sure it doesn't get driven negative by the other supply (I've blown up more than one supply by not doing this). The diode needs to be rated for a higher voltage than the supply and you place it across the output reverse biased, so it is normally not conducting.

Keep in mind I have no direct experience with this particular type of pack, but all Li-ion batteries have similar behavior. I bet Liveforphysics would know exactly.
 
eee291 said:
Why the heck do you need 116V DC?

Isn't 48v enough?

even if it isn't, I would try to get the cells to at least 48V before you buy yourself another power supply.

I was just going by the nominal rating. Ideally once it reaches a certain point the BMS would reactivate and take over, but I wasn't sure if I should be trying to trickle charge all the way.

fechter said:
Well, that's higher than any of my batteries, so I don't have anything that goes that high. The current sounds OK. Even 500mA would probably be OK to bring them up.

If you can measure the voltage on the pins, then it means you can charge through them. If you can access sections of the pack through the connector, then maybe you can find chunks that are under 60v and you can use your bench supply.

Another trick I've used before is to place another power supply in series with my bench supply to get more voltage. To do this you need to put a big diode across the output of the bench supply to make sure it doesn't get driven negative by the other supply (I've blown up more than one supply by not doing this). The diode needs to be rated for a higher voltage than the supply and you place it across the output reverse biased, so it is normally not conducting.

Keep in mind I have no direct experience with this particular type of pack, but all Li-ion batteries have similar behavior. I bet Liveforphysics would know exactly.

Thanks, I wasn't sure if I should expect those pins to be current-limited in some way. Hopefully for the trickle charge it shouldn't matter.

I'll start with my bench supply at 60V to get the ball rolling and see where I can get it.
 
eee291 said:
Sad to hear.

If you are up for it, there are a few guys who replaced their cells with Nissan Leaf cells.

Do you know who did this? I'd like to get in touch with them.

I just got word from Zero that they aren't going to do anything for me. Bike was purchased new in 2015, just months out of warranty, completely dead. I want so badly to like and support this company, but I can't justify anything other than the DIY route given their customer support.
 
https://endless-sphere.com/forums/viewtopic.php?f=8&t=82450

Also Dr.Bass on this forum. He is linked in the thread above somewhere.
 
eee291 said:
https://endless-sphere.com/forums/viewtopic.php?f=8&t=82450

Also Dr.Bass on this forum. He is linked in the thread above somewhere.

Thanks. My main concern is replacement cell voltages not lining up with the originals and the BMS not liking that. Good to know others have had success. Appreciate the thread link and Dr Bass reference. Good to know there are folks who've gone through this with Zeros even if not the exact same battery pack.
 
Today I applied +116V DC from a bench supply to the battery connection points on the bike. Bike did not turn on or give any indication of life from the dash display. Does anybody know if the bike needs to communicate with other pins on the battery interface? Or is this evidence that something else is toast as well?
 
What's the nominal Battery voltage? I thought it was still 48V, but I can't seem find anything on google.

I guess you could trace the 12V converters input back to the relay/solenoid, and bypass it to apply power just after the relay.
It might throw you a battery error light or something but it should be enough to check if it is functional.
 
eee291 said:
What's the nominal Battery voltage? I thought it was still 48V, but I can't seem find anything on google.

I guess you could trace the 12V converters input back to the relay/solenoid, and bypass it to apply power just after the relay.
It might throw you a battery error light or something but it should be enough to check if it is functional.

I think nominal is 102, max is 116. Don't quote me on those exact numbers, but they're close.

I've applied 12V directly after the DC-DC converter. Head and tail lights come on, but nothing on the display illuminates. In the Unofficial Service Manual schematic, there are two wires going from the battery to the MBB, but I have no information on what those wires convey, not even whether they carry data or a target voltage.
 
I didn't mean, apply 12V after the converter but 116V before it to see if the controller or anything else is powering up.

Also mind sharing the wiring scheme?
 
Back
Top