Schwinn S350 Controller Strangeness...

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AlexMI
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Schwinn S350 Controller Strangeness...

Greetings to all,

I'm learning a great deal just by reading through the forum entries here, have a question about an old Schwinn S350, found in a barn with a flat tire and dead batteries. I swapped out new batteries, of course (and confirmed that they should do the job perfectly, with both a voltmeter and by swapping them into an Izip). Before I fix the flat tire or do anything else, I'd like to know that the motor will actually run. When I power on, I get the green light, no problem. But turning the throttle... nothing. Taking everything apart, testing continuity on fuse, all connections, etc. The speed controller is where things get weird, because it doesn't look to be wired in any way that matches other descriptions I've seen here in the forums and elsewhere.

From the throttle, there are six wires. Not unusual so far, but the colors are gray, yellow, red, black, green, and red again. The wires actually split and connect to the controller via two separate connectors. On one connector, the gray, yellow, and red wires join into a five-pin connector, with the two free pins shorted by a small loop of blue wire. The five wires from that connector to the controller are gray, yellow, and red (matching the three coming from the throttle), and then orange and brown (the two that are shorted).

On the other connector, the black, green, and other red wire join to a three-pin connector, with corresponding black, green, and red wires leading to the controller.

I realize that one of these connectors most likely controls the main throttle function, and the other the power status LEDs, but disconnecting either makes no difference -- in both cases, the LEDs go out and the scooter is otherwise still dead.

There is NO brake lever connection that I can see. No separate line coming down from the brake (as I see on the Izip), no two-pin connector going into the controller. Even though I know this Schwinn S350 is supposed to have that feature, I sure as heck can't see it.

So the controller just has this strange two-headed connnection to the throttle as described above, as well as the main power connection (red and black) and the motor connection (also red and black).

I'm trying to narrow down where the problem might be, but I can't get around those throttle and controller connections. All I do know for sure is that the power is going to the main power light, to the LEDs next to the throttle, and definitely NOT going to the motor. (Checked with voltmeter.)

Any help untangling this strange assortment of wires (or for that matter, anything else to get this motor running) would be most appreciated!

Thanks again to all,

AlexMI

fahcue
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Re: Schwinn S350 Controller Strangeness...

I have one of these...if the back wheel turns nice and free, sounds like its time for a new ESC. Stick a battery straight to the motor wires to see if the motor is good. Lots of mods on mine I can get around 27-30 mph, not bad compared to 15 mph it is stock. FUN!!

e-doggies
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Re: Schwinn S350 Controller Strangeness...

Never seen nor heard of anything like this. Can't see a reason for two sets of throttle wires into the controller. Appears that someone was trying to match a 6-pin throttle to a 5-pin controller. That could have easily been done by connecting just the three correct wires and folding-back the other 2/3.

It was probably not in the barn because it had a flat tire. There's a very good chance the controller and/or the throttle need replacing. You can get a simple, better-than-Currie 24V or 36V controller for around $20. A throttle of your style choice is about $8.50.

I agree with fahcue, connect your motor directly to your batteries before you start spending money for controllers.

fahcue
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Re: Schwinn S350 Controller Strangeness...

Yep...that's the ticket, blow off that Currie crap and grab a generic from TNC, They have a 40 amp ESC most are only 30 amp. Get the 36 volt version and throw in another battery the motor will wake up big time. The throttle will work just use the three wires, the other three are for the leds you can't use these at 36 volts, but wow !! the new power is awesome, like I said I have one of these so I can give you tips as to what works the best. Let us know...good luck.

AlexMI
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Re: Schwinn S350 Controller Strangeness...

To Fahcue and e-doggies,

All forums on the net should be this helpful and encouraging! Can't thank you enough. I was out all day, will test the motor directly tomorrow. Assuming it's good, I realize that either the throttle or the ESC will need to be swapped out, and possibly both. (What do you make of this quick throttle test?
http://elescooterparts.com/scooters/Schematics/EleThroTest.html
Solid idea? Half-baked?) In any case, thanks again and I'll be back after I test that motor!

AlexMI

e-doggies
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Re: Schwinn S350 Controller Strangeness...

Yeah, I've seen that "throttle test" somewhere before. It sounded very familiar. I recall not completely understanding it when I first read it, and I still don't understand it now. I get confused about how to interpret item #4: "Make a circuit between the three accelerator / deraillur wires from controller
( This is where the three throttle wires mentioned above plug into the controller )"

I have a real problem visualizing exactly what that would look like. Doesn't really matter, if you have a voltmeter, there are better tests.

With the controller connected to a suitable battery pack, measure across the red and black wires in the 3-wire throttle connector coming from the controller. You should get around 5V. Connect those two wires to the matching colors on the throttle. Find the "signal" wire coming from the throttle and measure from it to the negative (black) on the controller. Voltage should vary from 1-4V as you roll the throttle. If not, you have a bad throttle, and maybe still a bad controller.

AlexMI
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Re: Schwinn S350 Controller Strangeness...

With the controller connected to a suitable battery pack, measure across the red and black wires in the 3-wire throttle connector coming from the controller. You should get around 5V. Connect those two wires to the matching colors on the throttle. Find the "signal" wire coming from the throttle and measure from it to the negative (black) on the controller. Voltage should vary from 1-4V as you roll the throttle. If not, you have a bad throttle, and maybe still a bad controller.

e-doggies,

My electrical engineering education continues here. I tested the motor, first of all, hooking it up directly to the battery. Runs just fine! So now I test the ESC and throttle, as per your suggestions above. Testing the red/black coming out of the controller, I get the 5V, no problem. Then testing the signal/black from the throttle, I get the 1-4V as I roll the throttle. So everything's checking out so far...

I think it's safe to say that the throttle is doing it's job, right? It's sending the right voltage to the controller. With everything else hooked up and turned on, though, the one thing that's NOT happening is that the controller is not finally sending any power to the motor. Unless I'm missing something else here, that seems to be the one broken link in the entire operation.

The actual connector from the controller to the motor seems to be fine, but I suppose I could try bypassing that? That's the only other thing I can think of, short of the next obvious step which is to replace the controller itself -- because it's not doing everything it's supposed to be doing. If that's the case... Where did you say I should look for a new controller? And if I decide to try the jump from 24V to 36V, is there anything else I need to be aware of?

Again, thanks to you and Fahcue. You are the best.

By the way, just for the hell of it, here's that 6-wire, split into 3 and 3, connected to 5 pins and 3 pins, throttle to ESC connection I was talking about.

scooter wires.jpg

(And remember, no brake lever shut-off! Very strange machine...)

(But like I said, we found it in an old barn...)

Thanks again,

AlexMI

e-doggies
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Re: Schwinn S350 Controller Strangeness...

Sounds like you have a good throttle. It's probably worth checking all the connections again, but the evidence points more toward the controller itself. 36V is a nice upgrade. TNC Scooters has lots of parts and has reasonable prices. They have quite a few 24V and 36V controllers. A Yi-Yun YK40-3 (36V) would probably fit in the nose of the battery tray. A Yi-Yun YK42-3 is much bulkier, but will give you even more power than the Yk40. I think these are in the $20-$30 range. Before you order, make sure you check all the other parts of the scooter to see if you need anything else. (tire, tube, chain, sprockets, etc.) so you can combine and save some shipping. Of course, if you upgrade to 36V, you will need a way to re-charge.

Thanks for the pic. About like I imagined it. Sure seems like someone has been tampering with it.

robert93
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Re: Schwinn S350 Controller Strangeness...

No Brake cutoff? Thats agianst the CPSC standards, no way that is production wiring. You need to find original documentation on the wiring. Verify that the controller is original, the motor is original, ect. Double check the brake levers for original. It may be possible that the blue wire is for the brakes and should be open unless under braking conditions, but, without the solid documentation to know for sure, its just guesswork.

AlexMI
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Re: Schwinn S350 Controller Strangeness...

e-doggies,

I see the 36V controllers on that site -- and I see that the wiring is pretty stripped down and basic, huh? (One positive lead going to both the motor and the power?) Should be simple to install, but what about that charging? I've looked around this forum just enough to see mention of more complicated charging methods, but wouldn't a basic 36V XLR charger do the job?

I hear ya on seeing what else the scooter may need and ordering everything at once. I'll certainly need a new back tire, but aside from that (and the 36V charger, if that's workable), I think it's all probably in decent shape.

robert93,

Original documentation is not forthcoming, as this scooter was abandoned in a barn and found God knows how many years later. Everything looks original is the strange thing -- with a Currie controller and even that brake seems to be factory. No way to know for sure, of course, but I do know that the brake wasn't tampered with. There's no place where a line coming out was removed or anything. I swear this scooter looks (to the untrained eye, admittedly) like it was manufactured exactly as I see it now, with no brake cut-off. (How old are those CPSC standards, anyway? This scooter may be more ancient than we think?)

Anyway, thanks again to all!

AlexMI

e-doggies
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Re: Schwinn S350 Controller Strangeness...

Alex,

The YK42-3 doesn't show a brake connector, but if you want that feature, you'd be better off with the YK40-3. It will have other connectors that you won't need to attach (brake light, charger, pilot light, etc.). You WILL NEED to close the "lock" circuit, though, or the controller will not operate.

You can charge with any 36V charger of about 2 amps or so. The "XLR" just refers to the type of plug on the end of the charger cord. I prefer parallel charging with one 12V automotive type charger. Once the wiring is done, I can charge any 24V, 36V, 48V (or more), battery pack with the same 12V charger.

Could you post a pic or two of your scooter?

fahcue
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Re: Schwinn S350 Controller Strangeness...

Mine doesn't have a brake cut off switch, these just didn't come with them period....power brake all you want!! Next for upgrades, I would get a freewheel sprocket also from TNC,($8) this will allow you to change sprockets, as the stock one is way too slow, look for a 50 some odd tooth sprocket with a 4 bolt pattern, I'm useing a 44 tooth but I'm only 155 pounds and there are no hills(Texas)so it screams past any scooter on the road. If you are heavy or lots of hills maybe a 60 ish tooth would work these are also cheap...I'm telling you mine flat out hauls a** I don't think going any faster is safe, 30 mph is a little hairy if you're not careful...but damn its fun!!

AlexMI
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Re: Schwinn S350 Controller Strangeness...

e-doggies,

It'll be the YK42-3, I believe, as remember there's no line coming from the brake in the first place. (And as per Fahcue, that was standard on this model! Standards, schmandards!)

Thanks for the info on the charging. This scooter does currently have the XLR jack, hence my assumption that's what I'd need. Although I hear ya on the alternate parallel charging. That sounds more ideal.

(It's dark now, will try to post some pics tomorrow!)

Fahcue,

Thanks again, and it's especially valuable that you have the very same model to work with. We're talking hilly upstate NY here, so yeah, more power = good thing. But if I understand your point about the freewheel sprocket... I mean, this thing has an 80 tooth sprocket on it right now. Is that not about as high as you can go?

How did you fit the extra battery and bigger controller in your S350, anyway? Stack them 3-high instead of 2-long? And then make your own alternate cover? (Don't tell me you got out an arc welder or some such thing and expanded the compartment. How much of a mad scientist are you, anyway?)

Good night to all,

AlexMI

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Re: Schwinn S350 Controller Strangeness...

Dang, there's a part of Texas WITHOUT hills? Family in Gillespie County (AKA the Hill Country) and Canyon Lake didn't get serious use out of some small electric scooters. Didn't make it up all the hills.

So I'm with Robert on the no brake cutoof issue: How does this even exist? Is there that little oversight? I'm not so sure on something as small as an S350 (I have one) that's important, you almost don't even need a brake. I'm not sure I'd want to go 27-30mph on it, not a stable design. I think mine is more like 12mph with some effort to mod.

WHo dares, WINS!!!!

AlexMI
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Re: Schwinn S350 Controller Strangeness...

Next for upgrades, I would get a freewheel sprocket also from TNC,($8) this will allow you to change sprockets, as the stock one is way too slow, look for a 50 some odd tooth sprocket with a 4 bolt pattern, I'm useing a 44 tooth but I'm only 155 pounds and there are no hills(Texas)so it screams past any scooter on the road. If you are heavy or lots of hills maybe a 60 ish tooth would work these are also cheap...

Okay, time out, answering my own question here. Less sprockets equals more speed, but less torque. So it's really a balancing act, factoring in rider's weight and the slope of the hills. If I've got a stock 80-tooth sprocket now, I could go less and pick up speed, as long as I'm not giving up too much torque. But if I do that, do I also need to shorten the chain? (Or is there enough play in the wheel adjustment that I can move it back to accomodate the smaller sprocket size?)

Sill learning here... Thanks!

AlexMI

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Re: Schwinn S350 Controller Strangeness...

OOPs, I may be wrong on the CPSC regs, i was thinking bikes..... I did do some digging and found that the S350 is a 2005 or earlier model, and had at least 2 controllers and possibly 3 throttles that arent compatible with each other. This may be the perfect time to just customize the daylights out of it. Find a controller that works with the motor, and set the rest of the scooter up to match the controller. Changing the rear sprocket? yep, gonnna need a chain tool to take some links out. Here's what I found
http://www.electricscooterparts.com/schwinns350parts.html

AlexMI
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Re: Schwinn S350 Controller Strangeness...

Robert93,

Yeah, that's a useful site for seeing the right parts, but I'll get the actual controller from TNC, as they have the generic 36V that will work in this scotter.

e-doggies,

Here are those pictures! The much-ballyhooed S350, left for dead in an old barn (consider this the "before" picture)...

s350-1.jpg

Note the flat rear tire and about-to-be-replaced bad controller...

s350-2.jpg

Note further the handbrake... (Look, Ma, no shut-off wire!)

s350-3.jpg

For comparison's sake, the handbrake from an i300...

i300-2.jpg

Said i300, bought used (note missing kickstand)...

i300-1.jpg

Finally, the very same weak-ass i300, fully charged, new batteries, etc., nevertheless failing to carry an 80-pound girl up this hill...

i300-3.jpg

Will the souped-up S350 have more luck? Stay tuned! As for tonight, I'm off to order some parts... Thanks again to all!

AlexMI

fahcue
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Re: Schwinn S350 Controller Strangeness...

If you have to buy new batteries anyway, just get 3 of the 7 a/h or some that are this size and they will all 3 fit in the tray. I have one mounted on the side that has the brake on it. I put a small shelf on the frame and used a large hose clamp around the battery and the frame to secure, you don't even notice its there because its black and doesn't look getto at all. Later.

AlexMI
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Re: Schwinn S350 Controller Strangeness...

Fahcue,

12V/7AH instead of 12V/10AH? Really? Wouldn't you be giving up power? (Or hours of use? Or something?) I figured stacking that third battery wouldn't be such a big deal, maybe just cutting down the deck size... But you tell me.

(Actually on first glance through the Internet, the 7AH batteries don't look much different in size than the 10AH, anyway...)

Thanks,

AlexMI

AlexMI
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Re: Schwinn S350 Controller Strangeness...

Greetings again to all,

After a short road trip, I'm back home and I've received the order from TNC. First of all, that YK42-3 controller, which looks like so on the website:
YK42-3.gif
Actually looks like this in real life:
scooter-test-1.jpg
I see from Googling another site that TNC has changed their wiring on this controller. As you can see, there's no more shared power line -- now a red and black for the batteries and a red and green for the motor. Same triple connector for the throttle, plus this extra little black and yellow connector that I'm not sure about. In any case, I figured the wiring is still pretty straightforward, so I gave it a try. Here's the trial run:
scooter-test-2.jpg
That black and yellow connector is not hooked up to anything (not that I'd know what to hook it up to anyway). It's apparently NOT the brake lever cut-off, because if it was left unconnected, the scooter would get no power, correct? In any case, the thing definitely runs now, but here's the further strangeness... The little green power light by the on/off button stays on at all times. (The scooter will run only when it's on, I mean to say, but even when it's off the green light stays on.) Beyond that, it's apparently not accepting a charge. This new 36V XLR charger isn't registering anything (red for charging, green for charged, apparently -- and it's not showing anything at all). So I'm just wondering what possible wiring mistake I may have made. Or if that unused black and yellow connector is somehow the issue here...

(Later edit: that yellow and black connector is definitely the brake shut-off switch, and it's completely optional. Doesn't have to be shorted or anything, just leave it hanging, etc. Still not sure how I managed to wire this thing so that the power light stays on. Also still not sure if this issue is also why the thing's not charging, or if in fact I've got a bad charger here. How can you test a charger, anyway?)

Nothing's ever easy, right?

Thanks again to all,

AlexMI

AlexMI
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Re: Schwinn S350 Controller Strangeness...

Charger is bad, on its way back. Meanwhile, power light is still on at all times, but that's not the biggest problem in the world. The scooter itself is tearing up the street, maybe a little bit TOO fast if you know what I mean. It does burn through a charge pretty quickly, too. But not bad for a broken-down machine that would otherwise still be sitting in a barn...

(I should shoot a youtube video or something to demonstrate how freaking zippy this thing is now...)

AlexMI

e-doggies
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Re: Schwinn S350 Controller Strangeness...

Glad you got it working! If the light is on when the switch is off, won't that discharge your batteries when you're not riding?

There should be a thin red wire going to the pilot lamp from the main rocker switch. I'm guessing you have it on the battery side of the switch so the lamp gets voltage all the time. If you move the pilot lamp connection to the controller side of the switch, it should come on only when the switch is on. If you (or someone in the pre-barn days) removed the flag connectors from the main switch, they may have been reversed when reassembled.

Yup, we want a video ...

DigitalCorrosion
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Re: Schwinn S350 Controller Strangeness...

Got the same scooter and pulled another currie throttle off. One has 5 wires and the other has 6. Cant seem to figure out how in the heck to get it working with twisting the handle. Connected a few wires and when I touch them the scooter will take off on its own but cant seem to get the proper wires connected to get it to work lol. anyone who can help?

Skutr469
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Re: Schwinn S350 Controller Strangeness...

Help Help! I know this is an old post I have a Schwinn s350 i'm trying to resurrect. Long story short if I plug the charger in, turn the scooter on I get a green light and the throttle correctly responds with rear tire movement. If I bypass the controller an alternate(19V) battery will power the motor. I have corrected most of the shoddy wiring, checked continuity but I cant get the alternate battery to work through the controller. Why does the charger make the scooter operate normally but battery wont . I cant post yet as I am new here. Skut

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