How to find a suitable replacement controller

[EdwinLove]

I have a smart Motion E-Urban (The brown one from 2012 -2013 according to https://www.smartmotionbikes.com/history/#year1) which I bought second hand about 10 years ago.

The controller has stopped working. The button to increase the power level is not responding so it is stuck at 0 and I can only get electric assistance by using the throttle.

How do I go about finding a replacement? Are they all different or is there any standardisation to them. I had a quick web search and I saw a number of controllers that had very similar looking connection. The model number on the back is C302-1404-D506 and it is 36V

 

[harryS]

Looks like a front drive bike with a rear battery? I suppose Smart-Motion ignores your queries? My borswer said their website was dead.


Well, the way to find a replacement controller is to post info about it. The above isn't very helpful. Need a piicture of its label, the wires. etc. Need pics of the handlebar control too. Is there a LCD display for speed/level? Is it just LED's,

However, I'll go out on a limb and say it's probably your buttons worn out. That's why you should post a picture of the buttons/control unit so people can tell what you're talking about,

For a bike this old, unless it's a real simple fix, I feel it's not worth going to an ebike shop, Replacing a conbtroller is labor intensive, It's the kind a thing a hobbyist with a lot of time can do.

 

[EdwinLove]

Close, is rear wheel drive with the battery on the rear carrier. I did email smart motion a week or so back but have not heard anything from them.

As far as I can tell, the handlebar control is the only controller and the one that I am talking about. Please see the attached photos. The rubber bit from the bottom button came off a few years ago and I used Gaffer tape to keep the water out. The rubber bits on the other buttons are disintigrating now.

Happy to do the work myself if necessary but need to know what I need to buy or how to fix what I have

 

[PedalUma]

The controller is the junction box of all wires and has mosfets and the motherboard. A display is very different. It resides on the handlebar and shows things such as speed and power level. If you want to find a replacement display go to google images and search for five-pin ebike displays. This one is very common for Bafang hub-drives. Get the model number and then search eBay.

 

[Gionnirocket]

Close, is rear wheel drive with the battery on the rear carrier. I did email smart motion a week or so back but have not heard anything from them.

As far as I can tell, the handlebar control is the only controller and the one that I am talking about. Please see the attached photos. The rubber bit from the bottom button came off a few years ago and I used Gaffer tape to keep the water out. The rubber bits on the other buttons are disintigrating now.

Happy to do the work myself if necessary but need to know what I need to buy or how to fix what I haveView attachment 203011View attachment 203012

No label on the back? Model #?
Is the motor and controller Bafang? If so most all of their UART displays are interchangeable.

 

[harryS]

If you drop your image so it is right side up into Google image search, it thinks it is a Bigstone C300 display. This AI search engine is pretty smart, It distinguished between the more common 3 button displays,



And maybe they are right, because this unitsells for a ridiculous price on aliexpress, indicating it is something obsolete.

Does the bike still run ... like the throttle works, but no pedal assist? Does that cable extension in your picture come out of the display or out of the controller? I assume you can still turn the bike on with the button on the display. Does the LCD light up?

The risk of buying a new display is that (a) it's overpriced and (b) may not work, You can buy a new display, controller, and probably a throttle and pedal sensor for the price of the aliexpree unit. You can check your own ebay.uk, etc, for a possible lower priced part,

I would see if the bike can run in default mode w/o a display. Many controllers will work this way with a default throttle and single PAS control, That requires a jumper on the connector, and is easy to do if the connector coming out of the controller has female pins, You would need a voltmeter to check the pins. Than buy a simple bike computer to read the speed.

More involved is replacing the controller and display, about the same cost as the above display.

You might even check in with this UK forum. They have some smart ebike hobbyists that might help and may know your brand,

Conversion Kits General Discussion

www.pedelecs.co.uk

 

[EdwinLove]

OK, thanks for the replies. There is no make on the device but the model number is C302-1404-D506 and it is 36V.

The display still switches on and the bike works fine with the throttle. The cable in the picture comes out of the display

So I assume this is the display and not the controller.

I'm attaching another photo. Is the controller is the black bit near the top on the bracket.

 

[harryS]

Looks like a well made bike, Is that the controller? I don't think so. Looks like a cable junction for the handlebars that they decided to clamp to the head tube.



The controller is probably inside the box that holds the battery, The battery slides out, no? Should be a compartment in front of the battery that holds the electronics.

You might check the pedal sensor first. Most of the early ebikes put them on either side of the pedals. It will have a disk with magnets and a sensor to detect that the pedal spins. A common fault is the magnet disk moved too far away from the sensor. I've seen the disks age and crumble after 10 years in the hot sun. Even seen them come loose and not spin with the pedals. Electrical faults can happen too.

The PAS sensors look like this. You might have a two piece unit with a separate disk or an intehrated one-piec part.
Two examples on the bike.


Finally, that google search could be wrong. I forgot I have this four button disolay with a brainpower controller. Cost me $50 USD for both display/controller about 6 years ago. I used it a few times. Didn't care for it, Looks similar to your picture. YOu can see what one controller looks like,

 

[EdwinLove]

Ah, yes, it makes sense if the controller is in the battery - here I guess

 

[EdwinLove]

Pedal sensor was replaced a few years back.
It worked fine about a year ago, I think it is just the buttons on the display. Would that be fixable?

 

[PedalUma]

I think it needs a new bike. Investing more in this is a lost cause; don't die on that hill. And I am not going to follow along.

 

[harryS]

Oh come on, PedalUma.You could refurb that bike for about the cost of a new one,

Meanwhile, for those whose time is cheap, check the PAS sensor signals to see if they flip as expected.

Does the display open up? Those buttons on the display are usually membrane switches. Sometimes capacitive.. Sometimes actual switch contacts. You have to be a wizard with soldering on surface mount circuit boards, but if you are, then it might be possible to parallel an external switch across the one that disappeared.