dead - bafang 750w with an 850c display

MikeR.

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Nuts, I think I have killed this thing.
After charging (followed instructions and turned the battery ON), I forgot to turn the battery off and installed it on the bike "hot". The display (850C) came to life, then swithed off, and now nothing works. It worked fine before this screw up.
As far as I can tell there is no fuse (probably would increase the price too much LOL). Is there an easy fix or do I have to start taking things apart?

bafang 750w with an 850c display

OK, it's been viewed by 30 or more people.. Does nobody have any clues what might be wrong? To be more clear, it is a Bafang mid-drive 750 watt, with an 850c display.
How do I check the controller? I can't look at error codes, or any settings, because the display won't turn on either.

This is a kit bought throught the WalMart so called "Market Place". The seller is shown as "Greenergy" . Neither of them are responding with any help. I HIGHLY recommend not using either Greenergy, or the Market Place, if you want any warranty help.
 

Capt Kirk

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You may or may not have damaged the 850 display/interface. You could purchase a cheaper bafang display, and reinstall it with the Battery "Unplugged" which is the advisable method when ever connecting or disconnecting electronic components. Or connect the display to a different motor controller. And "YES" "Greenergy" will not warranty any electronics once you have used them, and for a very large segment of the industry, this is the standard. As an electrical "Tech",the "NO Returns" policy for "Electronics" requires some knowledge of trouble
shooting before purchasing replacement components to prevent buying unnecessary "NON-Returnable" parts. As a retired electrician with both "Controls" and brushless DC motor experiance, I feel sympathy for the novice but when it comes to electricity, what you cannot see can still affect you and your stuff.
 

MikeR.

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Thanks for the replies. The get off and back on might work for a ferris wheel, but not this problem.
WalMart just denies all, and says the Greenergy company is no longer an associate. The sent me a link to Bafang, so I asked for help.
But I think I am done with them also, all I see on this forum is a bunch of people having trouble with these kits. If you know anyone interested in buying a complete kit (750 watt, 850c display, 48 v battery, etc, they can drop me a email at reebermp@gmail.com) I'm in Northwest GA, 1/2 way between Atlanta and Chattanooga, Tennessee.
 

Vinz

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I think the 850C has a USB port, and maybe your battery does too.
Turn the battery on and see if you can charge your phone from these ports. If you get a response from the battery USB, that could mean the battery is OK. I know it's a limited test, and may not provide useful data, but it's something I would check. I can tell you're bummed, and rightfully so.
 

MikeR.

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thanks for the reply, I can try the battery, but everything else is packed for the "return to WM" (which ain't going to happen! ) I might get ambitious and open things up.
 

Capt Kirk

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Hello, These units are actually pretty tough, but rules need to be followed. I know you got a small bundle invested here, but before you unload it, you might consider buying bafangs cheapest controller, You are talking less than $100, and after what you have invested and the owner of an 850 myself, I can only say that a cheap small controller will tuck inside the arc of the handle bars unlike the 850C which is mounted right out on top of the handle bars, and also the perfect contact point for an ass over roll down hill oops. Been there done that, hope you finish the project, I have 2 Bafang BBSHD's, and a brand new Luna X2 with the M600. I have had some issues(my fault) and some battery charger failures (theirs) (EBike Essentials) (Warranty hahahaha) but they have all been corrected (by me) and found a new supplier (LUNA) and now awaiting spring up here in Michigan.
 

MikeR.

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Vinz;
OK, I checked the battery. Usb port works fine, and a voltage check showes 52.4 volts. Pretty sure the battery is not the problem.

Capt Kirk: I have a query in to Bafang and am waiting for a response. I think the problem may be the 850c display. A lot of folks seem to have a problem with them. Unfortunately, as far as I can tell there is no way to check the thing out. A minimum dispaly was my thought also, but I will wait to see what Bafang says (if I ever hear from them).
PS: Your comment the rules must be followed is great. Except Bafang supplies absolutly no rules or info. The only place I have found an information is on this forum and on you-tube.
 

HumanPerson

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Nuts, I think I have killed this thing.
After charging (followed instructions and turned the battery ON), I forgot to turn the battery off and installed it on the bike "hot". The display (850C) came to life, then swithed off, and now nothing works. It worked fine before this screw up.
As far as I can tell there is no fuse (probably would increase the price too much LOL). Is there an easy fix or do I have to start taking things apart?

bafang 750w with an 850c display

OK, it's been viewed by 30 or more people.. Does nobody have any clues what might be wrong? To be more clear, it is a Bafang mid-drive 750 watt, with an 850c display.
How do I check the controller? I can't look at error codes, or any settings, because the display won't turn on either.

This is a kit bought throught the WalMart so called "Market Place". The seller is shown as "Greenergy" . Neither of them are responding with any help. I HIGHLY recommend not using either Greenergy, or the Market Place, if you want any warranty help.
Might have just blown the 850C display when you hooked it up without having the battery turned off Before hooking everythinbg up.

Go for the eggrider v2 display if ya can in my opinion, so you can then adjust more parameters in the controller.
 

MikeR.

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I am fairly convinced that the display is the problem. Now does anyone have any ideas how to test determine if the display is working right. Other than just replacing it?
 

Capt Kirk

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Vinz;
OK, I checked the battery. Usb port works fine, and a voltage check showes 52.4 volts. Pretty sure the battery is not the problem.

Capt Kirk: I have a query in to Bafang and am waiting for a response. I think the problem may be the 850c display. A lot of folks seem to have a problem with them. Unfortunately, as far as I can tell there is no way to check the thing out. A minimum dispaly was my thought also, but I will wait to see what Bafang says (if I ever hear from them).
PS: Your comment the rules must be followed is great. Except Bafang supplies absolutly no rules or info. The only place I have found an information is on this forum and on you-tube
 

Capt Kirk

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As a retired controls electrician, I was able to learn alot of this stuff and make my mistakes on "company" equipment. But my one rule is
"Never guess" on a Hot circuit. Always connect and disconnect components with power/battery off. And get as much documentation on the item as you can so you are making an "Educated guess" your odds are a little better. The Bafang website has color coded wiring diagrams and these also show the differences in the wiring plugs, which are NOT interchangable but can be modified to work with some soldering and insulating work. Learn how to use a multi-meter which will make people think you are a "jean yus" when you diagnose "opens" which are not as bad and "Shorts" which usually cause smoke, which is very bad. Truely hope this works out, as you will not be able to keep the "Grins" off your face when you are sitting on a working EBike
 

MikeR.

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capt kirk; yep! I agree with all you said. I also have a lot of experience with electric circuits. But I've was having a hard time finding any information. Yay for this forum!
Following several hints, and a circuit diagram I finally located, did as follows.
I had already removed everything from the bike so I did a bench test. connected only the throttle and the display and battery.
Nothing.
removed the display and ran a jumper from p1 - p2 in the display power cord. Viola! A little throttle and the motor runs.
Guess I will order a new display. And when the weather warms up a little, I think I will be ready to go. Meanwhile, I can put the bike back together.
just FYI the kit was purchased from WalMart Marketplace. NO help from them at all. They claim the seller, Greenergy is no longer an approved vendor, but they still offer this kit and other stuff from Greenergy, so buyer beware.

And thanks to everybody who offered help. :)
 

JimO

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Nuts, I think I have killed this thing.
After charging (followed instructions and turned the battery ON), I forgot to turn the battery off and installed it on the bike "hot". The display (850C) came to life, then swithed off, and now nothing works. It worked fine before this screw up.
As far as I can tell there is no fuse (probably would increase the price too much LOL). Is there an easy fix or do I have to start taking things apart?

bafang 750w with an 850c display

OK, it's been viewed by 30 or more people.. Does nobody have any clues what might be wrong? To be more clear, it is a Bafang mid-drive 750 watt, with an 850c display.
How do I check the controller? I can't look at error codes, or any settings, because the display won't turn on either.

This is a kit bought throught the WalMart so called "Market Place". The seller is shown as "Greenergy" . Neither of them are responding with any help. I HIGHLY recommend not using either Greenergy, or the Market Place, if you want any warranty help.
contact electromotive mods out of Phoenix. Rick Rowen sells batteries & electrical accessories. l believe is has an electrical engineering degree. He is a sharp guy and helpful. Good luck.
 

MikeR.

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Thank you everyone!
I followed a procedure re: run a jumper between p1 and p3 on the display line connector. result was the motor worked on throttle (that was all that was operable with the display disconnected ) . I ordered a new display (500c) and everything is back in operation. And I actually like the 500c better than the 850c. It offers everything I need and fits on the bike better. I now have room to mount a cell phone mount if I really want to.

Thanks again.
Now I have to figure out how to close this thread.
 

BBassett

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Thank you everyone!
I followed a procedure re: run a jumper between p1 and p3 on the display line connector. result was the motor worked on throttle (that was all that was operable with the display disconnected ) . I ordered a new display (500c) and everything is back in operation. And I actually like the 500c better than the 850c. It offers everything I need and fits on the bike better. I now have room to mount a cell phone mount if I really want to.

Thanks again.
Now I have to figure out how to close this thread.
I started with a BaFang display, then moved to an EggRider until it left me high and dry needing a software update, then I bought a 500C. The EggRider let me program the motor... something I did a total of one time and can do with a $10 programming cable. It can provide tons of ride data and help manage battery use, again something that I do myself with a Grin Satiator, but it was too small to see and I didn't like to buttons. The 500C is cheaper, easier to see and use while riding, doesn't require any updates, and most importantly gives me an accurate battery voltage. It's the input control I recommend to all BaFang BBSXX mid-drive owners. It's a good idea to find a used operable display that will work with a BBSXX to use as a backup and for testing purposes. When my EggRider crapped the bed I ordered a 500C, replaced the EggRider with the original BaFang display, and kept riding until it arrived.

https://photos.app.goo.gl/ADgC6oyPM2gyrCq27
 

Vinz

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I started with a BaFang display, then moved to an EggRider until it left me high and dry needing a software update, then I bought a 500C. The EggRider let me program the motor... something I did a total of one time and can do with a $10 programming cable. It can provide tons of ride data and help manage battery use, again something that I do myself with a Grin Satiator, but it was too small to see and I didn't like to buttons. The 500C is cheaper, easier to see and use while riding, doesn't require any updates, and most importantly gives me an accurate battery voltage. It's the input control I recommend to all BaFang BBSXX mid-drive owners. It's a good idea to find a used operable display that will work with a BBSXX to use as a backup and for testing purposes. When my EggRider crapped the bed I ordered a 500C, replaced the EggRider with the original BaFang display, and kept riding until it arrived.

https://photos.app.goo.gl/ADgC6oyPM2gyrCq27
I looked at your photos - that's quite some horse you got there!
But I did notice that on your 500C display, the battery graphical level is about half of the numerical level. (I assume you're using a 48V battery, thus the 52V reading.)
When I upgraded from a BBS02 to an HD, my graphical battery indicator dropped to about half the numerical value too. The numerical value seems to be correct. I have an 860C display, but also tried an 850C and a DPC18 - same results. Yes, I am using the same battery as before the upgrade. Don't know why this would be, but it does seem to be 'normal'. But it would be nice to have both levels match.
 

BBassett

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I looked at your photos - that's quite some horse you got there!
But I did notice that on your 500C display, the battery graphical level is about half of the numerical level. (I assume you're using a 48V battery, thus the 52V reading.)
When I upgraded from a BBS02 to an HD, my graphical battery indicator dropped to about half the numerical value too. The numerical value seems to be correct. I have an 860C display, but also tried an 850C and a DPC18 - same results. Yes, I am using the same battery as before the upgrade. Don't know why this would be, but it does seem to be 'normal'. But it would be nice to have both levels match.
2000Wh, 35Ah, 58.8V lithium packs (2058Wh to be exact). I charge to 56.8V (approx. 86%) with either a Grin Satiator or a solar panel and a voltage-boosting MPPT solar charge controller and don't discharge past 20% (45.4V) to extend the life of the packs. Apparently, it's working pretty well.

Stay safe.
 
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