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My bike went full throttle by itself?! (Video)!

S

Skedgy Sky

100 W
Joined
Nov 17, 2012
Messages
240
Location
New Britain, CT, USA
So I was chilling in my underground layer after spending over 12 hours fixing and modifying this Lyen 18FET 4115 controller (after it failed yesterday shortly upon receiving it in the mail) when all of the sudden...

[youtube]wvAZxbJ-k4w[/youtube]

And that "thud" you hear at 39 seconds is the wheel coming to a complete stop as a FET shorts out.
Soo... ....how and why? :?
 
Lots of things couldve gone wrong I guess, how controllers work are kinda a mystery to me, I would talk to Lyen because that kinda sounds sketchy. I had my bike go full throttle once after I was riding in the rain (dont ride in the rain) and my throttle was cutting out, I was going 10mph and it just went full throttle, 7kw to my rear wheel and flipped me off it like a rocket, the little board in the throttle got water on it and shorted the signal with the 5v causing it to go full throttle, I got a new throttle and will never ride or leave my bike in the rain again haha.

Talk to Lyen hes a pretty nice guy and very understanding when it comes to problems with his products.

Cheers,
Ugrd
 
I think it may be a firmware problem ( corrupted firmware? ) or some sort of problem with the mcu. Just a faulty input and WOT would not blow a fet. The throttle input is quite well ( software ) protected against WOT faults , unless its been turn off in the programming ( i think you can turn the protection off , but never tried it). A partial/intermittent short in the throttle is difficult to protect against but this will not blow a fet.

edit.. I can also see you have a CA.. do your throttle run through the CA , so this could also have been the cause of a WOT fault, but again it will not blow a fet.
 
Short on the throttle wires would do that. Other than that I am not knowlegable enough to say how it could happen internally.

Brushed motor controllers will fail WOT, I have one that does that intermittently. FWIW, when it does, ebrakes don't cut it off. :D
 
dogman said:
Short on the throttle wires would do that.
Click to expand...

it depends on controller, on Infineon controllers anything above around 4.0 volts on the throttle signal wire will shut the the controller down ( if set in software to do so and by default it is ), this may not be the case on all controllers. A short on the throttle will normally be vcc ( approx 4.8v )on the signal wire. most problems with throttles going high output is a physical fault with the throttle itself i.e magnets have come adrift and this will normally show a halve wot fault ( around 1.8v on the signal wire ).
 
I found no signs of any throttle shorts. I didn't even touch the bike for 10 minutes till it happened.
Throttle and CA were connected to controller same as any other bike on here.
If anyone didn't catch it, the mosfet failed AFTER I unpowered the controller. The settings on this controller are whatever Lyen gave me, unchanged.


Edit: So it turned out 1 mosfet failed. The last FET on phase closest to wires going out of controller.
I clipped the FET off, measured a few things to ensure no shorts, and applied power. I hear the "3 clicks of death" (as I'll call it) from the controller. It doesn't work. No throttle (but thankfully also no smoke).
Few minutes later (without changing anything) I apply power again. ...no "clicks of death".

I turn the throttle a bit and the controller works .. motor spins fine. I'm afraid of it though. I can't trust it to be reliable if it's doing all these things. :|

Edit 2: Left it alone for a bit. Came back to it. Applied power by touching ground leads together. *3 clicks* throttle doesn't work.
.. disconnected power.. let capacitors discharge... applied power again. No clicks, throttle works/wheel spins. What is up with it?? I didn't move any part of the controller AT ALL. It's still sitting on the chair.
 
3 clicks means you probably have a short from high to low on a phase (usually a blown mosfet or a solder bridge) and the controller is shutting down to protect itself. Discharge the caps and check for a short again.
 
zombiess said:
3 clicks means you probably have a short from high to low on a phase (usually a blown mosfet or a solder bridge) and the controller is shutting down to protect itself. Discharge the caps and check for a short again.
Click to expand...

Yes, I figured it was some sort of fault. ...butI am finding no shorts anywhere. It's more strange how it'll do the 3 clicks on one power up, then for the next like 5 power ups it works fine.
The last thing I want is me thinking it's working fine, then on the road the bike doing 100% throttle without my input.

By the way, thank you for the replacement mosfets you sent me. I instead ended up using them to fix this controller.
 
looking at the mess it's a wonder the motor spins at all :)
your floor remembers me of my work bench ... but what i TOTALLY avoid is crocodile clamps and unisolated connections. i burnt too much stuff that way and got more cautious. every time i connect a controller to the motor it has proper connectors soldered on.
it's not clear how and what you connected together but a short somewhere - a wire moving a bit and touching another wire can have strange outcomes.
 
izeman said:
looking at the mess it's a wonder the motor spins at all :)
your floor remembers me of my work bench ... but what i TOTALLY avoid is crocodile clamps and unisolated connections. i burnt too much stuff that way and got more cautious. every time i connect a controller to the motor it has proper connectors soldered on.
it's not clear how and what you connected together but a short somewhere - a wire moving a bit and touching another wire can have strange outcomes.
Click to expand...

I would have thought it's a wire moving too... except I had the controller on the chair untouched the whole time and was getting varying results. The only thing I touched was applying the ground aligator clip to the controller to power it up. .. and that doesn't move the controller... soo.. I don't know.
 
Skedgy Sky said:
Left it alone for a bit. Came back to it. Applied power by touching ground leads together. *3 clicks* throttle doesn't work.
.. disconnected power.. let capacitors discharge... applied power again. No clicks, throttle works/wheel spins. What is up with it?? I didn't move any part of the controller AT ALL. It's still sitting on the chair.
Click to expand...

i don't know if you read my post about mac pumping under load, and suddenly stopped working. during a longer steep climb the bike suddenly stopped and i couldn't turn it on again. just a short stuttering action when moving the throttle. when i got home, after testing everything fine with lyen's motor/controller tester, and reconnecting everything all works fine again. strange. really strange. and no obvious connection problems. all nicely crimped contacts (for hall and throttle) and super fit 5.5 bullets for phase and xt60 for battery.
 
I washed the board and dried it to get rid of anything that may be causing this problem for me.
After drying, I checked resistance again before going to plug it in. Resistance in and around phases and mosfets is good.

But.. I get 32.8 ohms on battery (+) and (-).

Searching around the board for what could be causing it, but so far I have nothing. :roll:

Edit: Ahhah. I have something..
+ to phase A is a short.
- to Phase a is 33 ohms.
I'm getting somewhere.. ..

..more dead FETs? But it was fine before I washed the board! .. still investigating.

...Nope. Found a piece of solder around phase A. Got rid of it. Wasn't related to 32 ohms on B+ and B-. :| Still getting 32 ohms on B+ and B- but everything else looks good. searching again...

TL;DR: Washed my board, dried it, and found a 32 ohm short. Resolved in post below.
 
Ok. The 32 ohm short on the battery rails is no more. Took a small capacitor. Charged it up to 90V, and applied to to power rails.

Everything looks good now, but I'm afraid it'll come back and haunt me as I don't know what the 32 ohm short was.
 
So you say that if it's clicking 3 times there is either a short on the phases or a FET died....

... I can't find any shorts anywhere.

The problem got worse. Earlier sometimes it would work and sometimes it would click 3 times. Now I can't get it to work. Clicks 3 times everytime I connect ignition. I'm unable to find any shorted mosfets.
 
Found a bad solder joint around the gate driver area!!

It wasn't till a few hours of poking at the board measuring resistances that my probe poked one of the ICs and it simply fell off. I soldered it back into place and CONTROLLER WORKS.[/size]!! :D

I guess the IC was making an intermittent connection. It worked sometimes, and other times didn't. After I washed the board the IC connection must have broke enough where the board stopped working all together.

I still have to put the controller back together, but the board as it is, laid out on the chair... works (for now).

Why the controller went full throttle yesterday, I still do not know.
 
Ghosts in the machine or gremlins. Take your pick.

Sicko me was expecting a wheels on the ground video of real carnage, tire marks on the ceiling kinda stuff. Glad there wasn't any damage other than the already blown once faulty upon arrival controller.
 
Thanks guys, controller is working now (and hope it'll stay that way). Had lots of wires breaking along the way because of how much I was handing it, but all is good now. 8)


fellow said:
Ever chased your bike up the hills after failed throttle resistor hack? Those damn head tube angles :lol:. I can't se no youtube film in your first post (using latest firefox)?
Click to expand...

I use Chrome and I see it fine.
Here's the link if you need it: https://www.youtube.com/watch?v=wvAZxbJ-k4w
 
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