Broken chinese 250W PAS eBike electric issue

I've had a lot if of problems with my Forca Arrow ebike i bought this fall from zawione-group.de for €1000.

Clearly they spent the whole budget of fancy looks and nothing on quality. The small mudguards constantly throws tons of mud on the controller and battery and the rider making it impossible to drive in the winter. The first ca 5 times (when riding in rain) the motor kept giving UNREGULAR/SHIFTING power to the hub wheel after about 5-15 minutes (and shutting down after about 2- 5 minutes more) The following ca 5 times the motor stopped working after about 5-20 minutes (when the ebike got to wet), and usually it started working again after i had dried of inside for a few hours. Now it wont start at all and i've checked everything and cant find anything broken of defect.


There are some small signs of corrosion on the 4 battery connectors, but only on the bottom half, not the part that touches the connectors in the battery.


I checked the controller (the weakest link). It was pushed into a way to small compartment.


but i could find no corrosion on the cables on the inside.


....and all the cables where waterproofed, the controller had water proofing where the cables entered and i could find nothing wrong inside the controller, except some "white grease", but i assume this white grease is suppose be there?


Neither could i find anything broken och burned on the controll-chip.

[youtube]L9E20ilK4PU[/youtube]
This video shows me starting the battery, then on the controller, showing that the push mode does not start the engine. Neither does pedaling (not in the video). But when i turn it of and spin the front wheel, it generates electricity which suggest there is nothing wrong with the controller or the wires, since the light goes to the front wheel through the controller (i think).

What can be wrong?
1. broken hub wheel (unlikely, only ridden about 500 km) but with a working generator that can power the light (has only ridden in rain/snow ca 10 times).
2. Something is wrong with "engine cutoffs" is the brake handels. and the engine wont start because it thinks i'm holding down the breaks (how do i check this)?
3. One or more cells is broken in the battery and it will only give me enough juice to power the light but the controller cuts of juice to the hub engine because it thinks the battery is so low it might take damage (this is not really consistent with the previous errors when it started shutting of when it got wet, and also the hardest and most dangerous to check).

can there be anything else wrong? what to check for fist and how!?

Welcome to the Forums.
Did you check / clean the pas-sensor and magnet-ring ( sits on the pedal-axle on the right ) ?
If so, did you check the connection of the sensor?
That would explain the unusual driving experience and shut down after few minutes, but not the misfunction in push-mode

Christian

yes i cleaned the sensor, there was a lot of mud on it. It could be possible to explain the un regular speed but on the other hand magnets should work just the same when obstructed, unless there where strong magnetic debris in the mud, which seems highly unlikely.

You have to start at the beginning:

• Charge the battery, remove the charger and check the battery voltage. It should be 41v to 42v
  
  Connect the battery and everything else. Switch on and check the voltage at the battery to controller connector. It should be the same as above.
  
  Keep everything switched on. measure the voltage between either the PAS or throttle red wires at their connector to the controller and the battery negative while connected. It should be 4v to 5v.

Please eport back the results, You can stick your voltmeter probes up the back of the connectors to get the reading while connected. Pull out any hot-melt glue if there's any there.

Thanks for the answer d8veh.

There is a 36V battery on this not 48V, i assume the voltage should be lover than 41v to 42v on a 36V battery?

i dont have a multimeter yet but i plan to buy this version version (Clamp Meter):
http://www.kjell.com/images/Product_130400106982275791/full/2/uni-t-ut201
http://www.kjell.com/sortiment/el/verktyg/matinstrument/tanginstrument/uni-t-ut201-p48113

is this the version i shall use? also comes with plyers but i assume the Clamp is the way to go?

Where is the "controller connector"? how can i identify it?

you should go to harbor freight and buy one of their cheap voltmeters. i am about to go use two different coupons for free meters from the sales newspaper they deliver in the mail. you do not need a clamp meter since you are not working on an air conditioning unit.

the white grease is thermal heat sink compound to increase the conduction of heat from the mosfet to the heat sink.

ultraboy said:

Thanks for the answer d8veh.

There is a 36V battery on this not 48V, i assume the voltage should be lover than 41v to 42v on a 36V battery?

i dont have a multimeter yet but i plan to buy this version version (Clamp Meter):
http://www.kjell.com/images/Product_130400106982275791/full/2/uni-t-ut201
http://www.kjell.com/sortiment/el/verktyg/matinstrument/tanginstrument/uni-t-ut201-p48113

is this the version i shall use? also comes with plyers but i assume the Clamp is the way to go?

Where is the "controller connector"? how can i identify it?

Click to expand...

They look a bit expensive. I had in mind something like this, which is less than $10:
http://www.ebay.co.uk/itm/Digital-LCD-Multimeter-Voltmeter-Ammeter-OHM-AC-DC-Circuit-Checker-Tester-Buzzer-/360538749861?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item53f1c8bba5

Follow the black and red cables that are on the outer two of the four pins inside the controller department. They are the main power wires to the controller. There will be a connector somewhere along the short path.

i bought a simple multimeter and tested the voltage coming out ot the 4 connectors in the bike that was connected to the battery


red - black 41V
black - yellow 41V
red - pink 41V

i could not find ANY other connectors to measure other than the ones going into the front light. They where 41V as well.


d8veh told me to "measure the voltage between either the PAS or throttle red wires at their connector to the controller and the battery negative while connected. It should be 4v to 5v."

How do i do this without cutting the wires of?? The PAS has one cable going into it,i cant open it up without breaking it (i think).



There is nothing open on the hubwheel. Do i have to take it of and take it apart to find anything to connect to?


There is a connector close to the hubwheel,it has 6 small plugs and 3 big ones. The holes on the other cable are to deep to get any measuring equipment inside.


Please advice how to i measure and where! Im lost!
Which is the "battery negative"?

You can check the 5v at that multi-pin connector in your last photo. Set your meter to 20v DC. Put the black probe on the battery black (0v) and then touch each of the 9 pins in turn. One should be 5v when the panel is switched on. Be careful to only touch one pin at a time.

Is the panel switching on OK?

The multi-pin connector (pin side) is connected to the hubmotor, not the battery, so that wont work!

Please assist!

Bummer you're having trouble so soon, esp on a cool looking frame like that. My guess would be under all that tape where the controller and wires are shoved into that tiny, hot, floodable little compartment, something as simple as one loose Hall sensor wire will shut the motor down even though all the lights look good. I've been working on a bunch of cheap Chinese mopeds, and three in a row had the tiny tab broken that holds the terminal into the plastic plug , then when the plugs were shoved together and stuffed and twisted in there (and on these hit by the loose DC/DC converters just flopping around unmounted) the terminal backs out. Or in your case, maybe a PAS wire.. theres no throttle right? Just the PAS? The brake cut off wires are a good place to check too,, pinched and shorting is another lights-all-good motor stopper. Which btw, your front brake cable looks really tight between the lever and the sliders, prob goes looser when you're on it, but it will yank as the fork drops into potholes. or maybe the pic angle doesnt show the curve..
On a side note, whats peoples take on cast fork dropouts breaking with front wheel motor? It would seem like with regen esp. yanking the axle back and forth that thats a lot of stress there it's not meant for, and not seeing any torque arms? Maybe 250w isn't enough to worry about?

ultraboy said:

The multi-pin connector (pin side) is connected to the hubmotor, not the battery, so that wont work!

Please assist!

Click to expand...

You sick your probe in the holes, not the pins.

ultraboy

The multi-pin connector (pin side) is connected to the hubmotor, not the battery, so that wont work!

Please assist!

Click to expand...

I understand your dilemma, your new to this stuff. Are you in Stockholm. I have fixed a few of those chinese ebikes, I can help you check the motor, controller, PAS etc.

Thanks for all the answers!

I still have no idea whats wrong!

I followed Voltron's tips but and checked all the wires again under the tape but i coyld find no loose wiring.

I tried opening the LED battery controller but is was impossible, i even removed the stickers but there where no way of opeing it!

i have this LED controller:

I have narrowed it down too the multi-pin connector or the hubmotor. I have nine pins. the middle one gives ca 41V, 1 of the other eight gives about same; 41.1V, 1 gives zero and the other 6 gives around 39.5V. I have NO idea how to interpreting this.

Follow the wire on the connector (the female with holes) until you come to the controller. Unplug it and measure the voltage on the 5 thin hall sensor wires.