Byocycle Chameleon FD folder controller/display problems

raj1

Just Joined
Sep 4, 2020
3
0
Hello all, I have just found this excellent site and wondered whether anyone has any pointers on an issue with my Byocyle Chameleon FD which I bought second hand a few months back.

The bike was working beautifully until:

a) I had recently taken it on a long journey in the car, however it was still working for a few days after this.
b) I (fully) charged the battery (I am not sure if this is a coincidence).

Now, when I press the power on button, all the LEDs on the display come on. The bike gives what appears to be assist level 1 – so the motor is fine.

If I press any of the buttons on the display, (headlights, assist level etc) then the bike turns off. I am not able to turn on the headlights or change the assist level.

I have checked all the cable harness connections are correctly mated

I was wondering if this is a known fault, and if it is what the solution is. Is it likely to be (display, controller or cable harness)?

The bike has what appears to be a kingmeter 791 display (unbranded with walk assist) as shown in the photo, which I believe runs with a Lishui controller.

Additionally, does any one also know a good source for spares of these parts ? I have been unable to get any response from Byocycles by either phone or e-mail and it is not clear that they are still trading ?
 

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vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
Those meters are a standard part. There are several similar ones that work the same. They fall into two categories, which are those that are digital and communicate with the controller, and analogue ones that are dumb. The 791 can be either, but is most likely analogue.

They all have a red wire that comes from the battery and a black ground to power them. They all have a blue wire that is battery voltage when switched on, which powers the motor controller.

The Analogue ones have a green wire that sends a different voltage for each pedal assist level. If it has a lights switch, the 5th wire carries battery voltage when switched on.

The digital ones have two comms wires, Rx and Tx that carry micro-pulsing 5v. those wires are normally green and white.

You can tell which type you have by measuring the DC voltage on the green wire. Analogue would be 1v to 4v and digital would be zero. That's if they're working, but your isn't, so that might not tell you anything. In that case, you have to open either the controller of the LED panel to see the markings on the PCB. The digital one will be marked Rx and Tx where the wires are soldered to it.

Whichever type you have, you can always get level 1 PAS and throttle operation when the blue wire is switched on, so you can remove the panel and bridge the red and blue wires to get a basic function while you sort it out.

Once you've figured out what type you have, a replacement is easy, though there are three different types of connector as well, so you might have to cut the connectors off and join the wires.

The cause of your problem is water inside the panel or a wire pulled off. The water often wipes out the CPU and that can't be repaired.
 

raj1

Just Joined
Sep 4, 2020
3
0
Those meters are a standard part. There are several similar ones that work the same. They fall into two categories, which are those that are digital and communicate with the controller, and analogue ones that are dumb. The 791 can be either, but is most likely analogue.

They all have a red wire that comes from the battery and a black ground to power them. They all have a blue wire that is battery voltage when switched on, which powers the motor controller.

The Analogue ones have a green wire that sends a different voltage for each pedal assist level. If it has a lights switch, the 5th wire carries battery voltage when switched on.

The digital ones have two comms wires, Rx and Tx that carry micro-pulsing 5v. those wires are normally green and white.

You can tell which type you have by measuring the DC voltage on the green wire. Analogue would be 1v to 4v and digital would be zero. That's if they're working, but your isn't, so that might not tell you anything. In that case, you have to open either the controller of the LED panel to see the markings on the PCB. The digital one will be marked Rx and Tx where the wires are soldered to it.

Whichever type you have, you can always get level 1 PAS and throttle operation when the blue wire is switched on, so you can remove the panel and bridge the red and blue wires to get a basic function while you sort it out.

Once you've figured out what type you have, a replacement is easy, though there are three different types of connector as well, so you might have to cut the connectors off and join the wires.

The cause of your problem is water inside the panel or a wire pulled off. The water often wipes out the CPU and that can't be repaired.
The PCB is labelled:
VCC (red wire) - obvious
GND (black wire) - obvious
K (blue wire) - assume this is control power to the controller
OUT (green wire) - assume this is analogue control voltage
HR (yellow) - assume this is the headlight control, however this goes to the controller rather than the headlight directly.

It would be good if you can confirm my assumptions. But my main question is how does the walk assist work? Does the display send a different "special" control voltage when in walk assist (6km/h) mode?

I was unable to get any response from Byocycles so have ordered the following:


Which appears to be the same (still waiting for the delivery), but has a 6 pin connector. Is the walk assist likely to be separately signalled on this?

The controller label says that "Throttle adjustmet voltage" is 1.2V to 4.4V. Is this the same as "assist level".

Controller is LSW914-16-18L.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
I think you might have figured it out correctly, but I have some reservations. If it's an analogue one, the green wire gives an analogue signal to the controller for the PAS speed. For a three level one, it would be something like 1v =level 1, 2v = level 2, 3v =level 3 and 4v = 4mph. I've never tested a 5 level one.

I have some reservations because it has 5 wires and 5 levels. If you hadn't shown me those markings, I would have said it's a digital one with green being Tx and yellow Rx. These switch the lights on with a data transmission rather than a direct signal. One could interpret "out" as transmit and "HR" as something receive.

A 6 wire panel would be digital, with the 6th wire working the lights by direct battery power to the lights, i.e. the panel switches and powers the lights directly.

Are those markings that you listed on the panel pcb or the controller pcb? Whichever it is, you need to look at the markings on the other to confirm whether it's analogue or digital. Normally, it would say Tx and Rx for the data wires, but if yours is digital and the markings are "out" and "RN" at the other end, "out" one end would be connected to "RN" at the other end and vice versa.
 

Crippsy77

Just Joined
Jun 17, 2022
1
0
Hello all, I have just found this excellent site and wondered whether anyone has any pointers on an issue with my Byocyle Chameleon FD which I bought second hand a few months back.

The bike was working beautifully until:

a) I had recently taken it on a long journey in the car, however it was still working for a few days after this.
b) I (fully) charged the battery (I am not sure if this is a coincidence).

Now, when I press the power on button, all the LEDs on the display come on. The bike gives what appears to be assist level 1 – so the motor is fine.

If I press any of the buttons on the display, (headlights, assist level etc) then the bike turns off. I am not able to turn on the headlights or change the assist level.

I have checked all the cable harness connections are correctly mated

I was wondering if this is a known fault, and if it is what the solution is. Is it likely to be (display, controller or cable harness)?

The bike has what appears to be a kingmeter 791 display (unbranded with walk assist) as shown in the photo, which I believe runs with a Lishui controller.

Additionally, does any one also know a good source for spares of these parts ? I have been unable to get any response from Byocycles by either phone or e-mail and it is not clear that they are still trading ?

Hello!!! i have recently had the same problem you had. Did the new controller unit fix the issue? and im curious as yes you`re right its a five pin [Green} and the 5 standen 36V LED display has a 6pin?

Please let me know how you got on? and what options i have?

thanks