Leader fox arimo maybe the controller is broken


New Member
I bought a gift for my girlfriend's son, a used Leader Fox arimo bicycle. In the Netherlands recently, I thought that in the first place the seller is honest, in the second that even if there will be any problems I will find a workshop and eliminate the breakdown. But I was wrong, no one wants to repair this bike.
I have no experience with electric bicycles. When I bought it, it worked, but it didn't display the battery level. The seller said it was because of the new display, I also have the old one on hand with a crack, it's not it, I swapped the old and the new one, the problem doesn't go away.
The problem:
After 2 weeks after purchase, error 01 appeared (manual says it is communication error). I removed the battery and took out the controller to see if there was a loose contact. I found nothing, reassembled the bike and the error went away. If I press and hold the minus button, the motor starts to run at 6 km/h. But now the bike does not respond to pedal movement. I assume that the problem is in the controller and I want to replace it, but I can't find such a controller on the internet.
I think the problem is in the controller as the motor works, after I wiggled the contacts in the controller error 01 went away but now the bike is not responding to pedaling. I thought it might be the hall sensor, but it was working before I tried to deal with error 01.
What can I do in this case if I can't find this controller on the internet? Is there any way to install a different controller than the native controller?





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Does the 6km mode still work?

Check your brake levers to make sure they're not loose and allowing the on/off switch in them to shut off the controller. You can always unplug the brakes to eliminate that possibility, However. since 6km worked, the brake switches are probably not engaged.

You might have had a bad display connection, but in your disassembly, you might have disturbed the pedal (PAS) sensor connection. If you have the tools/skills, like a multimeter, you can verify the PAS sensor has volatge. Usually are 3 wires, power, ground and signal. Power is 5V, Signal will pulse between 5V and 0V when the pedals are turned. And of course, you want to be in an active PAS mode for the bike to respond. If the sensor uses a separate magnet disk, make sure it didn't get moved away from it. They have to be close to work, unless it's an integrated sensor.

These are pictures of a PAS sensor with separate magnet disk, and one that is fully intehgrated.
marav.jpg type2.jpgtype1b.jpg

If your bike has a throttle, you could check that too, but I guess they're not found on Euro ebikes.

Controllers can be swapped, but it's a lot of wiring for most people. You also have to buy a matching display for the new controller.
Looks like the controller has taken on moisture. I can tell from the smeared ink on the label and the backside of the pcb. I would get a new display and controller combo.

Also noting that there is a red led on your controller. Red lights, in general, are not good, but I haven’t seen that in the controller board.

When you hold the down button and the motor spins, your motor is most likely good. It doesn’t sound horrible.

Before purchasing a new controller, measure the physical size of the current one. You’ll want one close to that size, so it’ll fit into the downtube. KT controllers are very nice and have many types of displays. You might get lucky and find one that you can plug in and it’ll work. Mostly, there is some rewiring that will need to happen. Usually the phase wires, throttle, or PAS will need some attention.
All those pictures, one of the part critical to match up. The connectors to the motor, pas pickup, brake handles, display. You will have to buy a matched pair controller and display. Connectors go through fads so buy them while they are hot. Or not. You are in luck, juli connectors (round) are the fad of the minute.
I can generally find no controllers with display stocked inside the USA. The ones I buy don't even connect to a pas pickup. Throttle only. Sending my birthdate and debit card number to the land of counterfeiters & hackers is not something I will do. If aliexp wants my birthdate, they can pay for a credit report. You may not have enough assets to be worth hacking. There are throwaway pay cards, and paypal for the debit card problem. Amazon may have something, but since they made their freight double what UPS charges I don't use them. Their drivers are as dangerous to bicyclists as pizza delivery men. I don't need their free soap operas either. The last year amazon website locks up my op system if I look at a iink, so I don't do that either.
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Thank you all for your help.
I ordered the set, controller, display, pas sensor and brake handles (the handles were unnecessary as the bike has hydraulic brakes and the handles in the kit are for the pads).
I swapped the controller and display first, leaving the pas sensor native. The bike worked, but started to jerk violently when I tried to ride it. Then I glued the pas sensor from the kit and the bike started working perfectly.
Problems I encountered, first of all the kit comes with "5 in 1 cable" which is unrealistically long, apparently it is assumed that this controller should be in the back of the bike, on this bike it can only be installed at the top of the frame near the handlebars, so I hardly put it there with this cable.
In turn the cable for the motor is short and I bought an extension cord for 10 euros, and even with the extension cord it was barely enough.
But that's not so important, the main thing is that the bike works amazingly well now


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