Help me find this Controller

aDZ1968

New Member
Region
United Kingdom
I brought my wife an E Trends City bike for work and last week it stopped working under the battery housing is the controller with no protection as such I now know they are useless, I have tried to get them to see if they can source me a new controller but they dont bother replying.
Anyway I have added some photos of the controller it does not seem to have a Motor Hall but it does have a 4 pin that goes to the battery rear wheel area but I cannot find similar or the same anywhere any help would be amazing
I anyone can help please also if you need any more photos 🙏
 

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36 v 15 A, pretty common. Low brake pretty common. The red black to battery is weird, but you could cut it off and replace with two crimp on 4 mm bullet connectors or ring terminals if the replacement has that. The 6 terminal could be to a display but you did not say you had one.
The 4 terminal, that is not normal. Don't know why it would go to the battery rear wheel area. If it actually goes to the two brake handles for shutoff when braking, you may be able to adapt something else. Cutting soldering hiding in shrink wrap tubing. I buy controllers on E-bay. Most of those require a "door switch" between the alarm power red and the enable input which has various names. I have found no source of those black side terminal connectors. Is there a battery cutoff switch? If not the controller will run down the battery in a week or two if left on. Some displays with a touch screen will turn on and off the controller. Is there a PAS pickup near the crank? A magnet wheel? Those are usually 3 terminal. Is there a throttle? those are usually 3 terminal.
 
Let's see a photo of the motor connector and the matching connector from the controller. Four pins doesn't seem right. Either 3pins, 5pins or 6pins is typical. Not talking about the thick blue, green, and yellow wires that use bullet connectors. If it is 4 pins, I'm not aware of any like that.

Is this the bike? Uses the 810LED handlbar unit?

.What's wrong with it? Does it power up and not move? Does it not power up?

Common reasons for a working ebike not to work
-Brake levers are engaged, activating the brake switches that inhibit the motor.
-Loose connectors.

It's rare to burn out a motor, especially on these little bikes unless you are pretty abusive.
.
 
Let's see a photo of the motor connector and the matching connector from the controller. Four pins doesn't seem right. Either 3pins, 5pins or 6pins is typical. Not talking about the thick blue, green, and yellow wires that use bullet connectors. If it is 4 pins, I'm not aware of any like that.

I think that this connector is going to the motor.
Three hall sensor wires, (green, yellow, blue) positive (red) and negative (black) to power the hall sensors.

Screenshot_20241016-131111_DuckDuckGo.jpg


The speed sensor wire is either on a separate wire to the motor or on a magnet on the wheel.

And the three phase wires running to the motor, with black and red going to the battery,..

Screenshot_20241016-143841_DuckDuckGo.jpg




A KT controller and display will install quite easily if the OP can't fix the problem or source a replacement controller.
 
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If the 5 pin goes to the motor, then the 4 pin goes to the display/control on the handlebar. I have never seen that connector for the motor. I have never seen any controller compatible with the display/control. I you buy a KT, you'll have to buy a KT display to turn the controller on and off. Also replace the motor connector with something you can buy, like white rectangular connector with pins that solder on. I found a kit of those, 2 pin, 3 pin. 4 pin, and 6 pin blocks male & female, on ebay. Called "ebike scooter connectors".
DO NOT buy a controller with more amps. If you have many hills or ride fast, you can burn a 15 amp motor up. I have shorted out two motors, one a 36 v 350 watt, one a 48 v 500 watt, with 25 amp controllers.
 
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I think that this connector is going to the motor.
Three hall sensor wires, (green, yellow, blue) positive (red) and negative (black) to power the hall sensors.
No doubt here that you're right, but the OP says he has a four pin.
If the 5 pin goes to the motor, then the 4 pin goes to the display/control on the handlebar. I have never seen that connector for the motor.
I've had two store bought ebikes that used the flat JST 5 pin connector for the Hall sensors, but I have never seen a stand-alone controller offered for sale that didn't use a white 2x3 Molex for the Hall's. Some splicing will be needed,

He does need to show what the bike uses to turn pn, whether it is an LCD display, an LED display like the 810LED, or just a button on a throttle.

If he's mixed up the 4 pin and 5pin, it's probably like this 36V controller I pulled off an inexpensive ebike.
ecotric_controller.jpg
 
If you buy a KT, you'll have to buy a KT display to turn the controller on and off.

Yes, a KT controller needs a KT display to operate properly.
It's more than just on and off.

Also replace the motor connector with something you can buy, like white rectangular connector with pins that solder on. I found a kit of those, 2 pin, 3 pin. 4 pin, and 6 pin blocks male & female, on ebay. Called "ebike scooter connectors".

I think that might work, but he'd probably still have to cut wires to attach the connectors?

He could bypass the connectors and connect the wires together directly then shrink tube.
That's what I did. It's way more weatherproof.

DO NOT buy a controller with more amps. If you have many hills or ride fast, you can burn a 15 amp motor up.

A controller with more amps may be too big to fit as well?

This is the smallest KT controller.
It's got the connector that you mentioned,..

Screenshot_20241016-211840_AliExpress.jpg
Screenshot_20241016-211528_AliExpress.jpg
Screenshot_20241016-211646_AliExpress.jpg
 
If he's mixed up the 4 pin and 5pin, it's probably like this 36V controller I pulled off an inexpensive ebike.
View attachment 184283


I think that's what he's got,..

IMG_2626.JPG



It's even got the gray wired connector, probably the speed limiter.
I guess that's instead of the typical white speed sensor wire?

That's the one that you unplug to go Really Really FAST !!! 😂

If the 4 pin connector does go to the display, it's probably a very simple display.
 
He does need to show what the bike uses to turn pn, whether it is an LCD display, an LED display like the 810LED, or just a button on a throttle.

I found this picture,..
I think he's got the 810LED?

Screenshot_20241016-215221_DuckDuckGo.jpg


I don't know how that display operates?
 
The controller I showed runs off an 810LED too, the simple 4 wire version. If he had an 810 LED, the 4 wire model is easy to test to make sure it works,

Unless he let water get inside, controllers are pretty tough, I know, because I've drowned 2 or 3 of them. I think it's worth knowing it's bad before replacing it, as they are hardly ever plug and play,
 
On your ebay-inna-uk, there are a number of controllers witj 810LED's that would work. but they ship out of China. There are a few with the 810H which is similar but the advantage is UK sellers,like this one, I picked this one because the listing had the connectors labelled.


What's gonna happen anyway is that you will have to cut the 5 pin motor connector off the old one, and splice it in place of the white 2x3 pin connector found on most third party controllers. It will be wire color to wire color.

Instead of buying something like the above, consider a KT controller as suggested by indianajo. You will also need to buy the matching KT display. This will give the bike a smoother 5 level pedal assist. Tradeoff is it cost 3X more.


You can save money by going to a cheaper display/controller. The dreadded s866 and brainpower controller.


However, before you start throwing money on parts, you should be sure it's a bad controller.
 
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On your ebay-inna-uk, there are a number of controllers witj 810LED's that would work. but they ship out of China. There are a few with the 810H which is similar but the advantage is UK sellers,like this one, I picked this one because the listing had the connectors labelled.


What's gonna happen anyway is that you will have to cut the 5 pin motor connector off the old one, and splice it in place of the white 2x3 pin connector found on most third party controllers. It will be wire color to wire color.

Instead of buying something like the above, consider a KT controller as suggested by indianajo. You will also need to buy the matching KT display. This will give the bike a smoother 5 level pedal assist. Tradeoff is it cost 3X more.


You can save money by going to a cheaper display/controller. The dreadded s866 and brainpower controller.


However, before you start throwing money on parts, you should be sure it's a bad controller.
Thank so much I need to check this one first as you said I was just Peed off at the design of the bike so probably rushed putting it back on
 
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