Cube Agree Hybrid C:62 - Fazua Drivepack Issue

[mattgod69]

I hope you are all ok and you had a good Easter.

I have a Cube Agree Hybrid C:62 Race Disc E-Bike 2019.

My Fazua system stopped working over the weekend. I obviously noticed this mid ride when the assistance was gone…. I also noticed that the top led was intermittently flashing red. I charged the battery (it was about 40%) in case that was the issue.

I plugged the drivepack into the PC and ran the toolbox. I wanted to check if there was a firmware update too, but it is up to date (2.12). Running diagnostics with the drivepack out and in the bike gives the following error on each test:

hard fault 20 - driver board FET shorted

I noticed this am when trying the bike that it is very difficult to move backwards, it moves forwards without issue.

I also noticed yesterday that the white LEDs around the power buttons were dim, although this seems to have returned this am.

I cleaned the contacts on both the pack and bike but these looked ok anyway.

Does anyone have any ideas what is going on and what I need to do to sort it out?

Has anyone had a motor failure?

Many thanks in anticipation and for your time.

Matt

 

[Deleted member 4845]

You appear to have blown a FET. This is a component in the controller for the motor, they can blow in a couple different ways, but all are bad. You need to either install a new FET, board-level soldering, most likely, or get a replacement controller.

Determining what caused it to blow would require a LOT more diagnostic info than you have currently supplied. The fact that is stiff moving backwards is interesting, if it does this with the battery removed it will point to additional issues.

Although, with no link or info about the hardware, no knowledge of the bike's history, usage profile, incidents of accident or abuse, details of last successful ride, details of moments before failure, and most importantly, no mention if it ever caught on fire, it is difficult to guess with any expectation of accuracy.

You are likely to find out why I strongly recommend making sure ALL components are generic and aftermarket replacements are easily available. Most controllers are well under $100, yours is likely significantly higher than that.

 

[jhonmartin692]

What is the most likely cause of a FET blowing on an electric bike controller?

 

[mattgod69]

Thank you for your messages. The bike is just over two years old has covered just over 4000 km from new, has been well maintained and only gets written in the dry, although I have been caught out a couple of times in the wet, although not severely. It is a road bike, so only gets rid on the roads.

There are no accidents or abuse, the only thing has happened is that the motor has hit the ground a couple of times when trying to fit into the bike, although I think this is fairly common as it is quite heavy and difficult to fit, particularly with the older catch system. Obviously, it doesn't fall from a great height as it is not far off the ground from being fitted, still not ideal and is obviously avoided as much as possible. The unit must be able to withstand some battering though as this system is fitted to mountain bikes!

I only noticed it when I was riding close to home this and the assistant suddenly stopped. It had been working without any issue. There was no noise, no bang or anything, it just stopped working, certainly no fire or smell of burning. I then noticed that the LED was flashing red on the LED unit on the handlebars. Thinking back, the unit has played up a couple of times where it has not been working at all. However, turning of the battery and the LED controller and restarted the system always got this problem sorted out.

When the dry pack is removed, the bike can move forward and backward easily. The issue is definitely with the drive back.

The manufacturers are responding. They are saying to send the unit back to them in Germany. They are saying that the driver board of the motor which has a problem and it is not a common issue.

 

[Deleted member 4845]

FET's generally blow due to excessive heat, excessive power demands, or just an internal fault. Controller installed inside the motor is more prone to such problems. Controller not getting good airflow is more prone to such problems. There are also FET's of higher, and lower, quality, and also differences in power-handling capabilities and efficiency.

The information in the second post should have been in the original one.

Depending on shipping costs, purchasing a new replacement may be a cheaper way to go. Unless the controller is in the motor, then the install is significantly more difficult, time-consuming, and costly. However, depending on what the Germans will charge you, still may be more cost effective.

Noting the pre-existing problems before the total failure, I would get an entirely new controller as opposed to repairing this one.

Stiffness going away with battery removed indicates that the phase wires are not shorted and there is no internal mechanical obstruction, as from a clutch or gear pieces, which a Direct Drive motor does not have, but we do not know what type of motor this is. That information has not been supplied.

As for this being a common issue, well, among hi-performance users, it is definitely a well-known problem. Some people have resorted to an oil-fill cooling system, heat-sinks, fans, etc. Heat is the main cause of the issue.

 

[mattgod69]

Hi Nelson, thank you for the detailed response and info.

Fazua are as usual being good at responding, i am thinking this might be done under warranty (even though it expired i think two or three months ago). i will keep you posted.

I agree, if they do not repair or replace, a totally new controller would be best.

How do you cool the Fazua system? It is completely sealed? i do not think there is any way this would be done and i have never noticed the drive pack getting anything other than warm.

Many thanks once again.

 

[Deleted member 4845]

There is a controller, a motor, and a battery. Not sure what you mean by "dry pack". Sometimes controller and battery are in one box, sometimes ALL are inside the motor, sometimes just controller is inside the motor.

I can't see it from here.

Heat in the battery not generally a huge problem. Controller needs to have good airflow. They are somewhat water resistant, but MUST have airflow, higher the wattage, higher the heat. You can fill the controller with a potting compound to make waterproof, but no longer repairable. OK on a low wattage system, they make less heat.

You likely have less than 6-8 Fets, larger controllers can have over twice that. FETs make heat. Found no details on your specific controller and I am not going to hunt any harder.

Information on your motor, battery, controller, and locations of same is information you need to supply. I glanced at a webpage, as you supplied no pictures, description, link, or details, and the exact location of components and power levels is unclear, but very likely a low-power system. Controller may be extremely difficult to replace. Potting or epoxy fill likely a workable waterproofing method, though that would worsen any pre-existing heat issues. Which may, or may not, have caused your current failure. Sometimes FETs just fail. Getting wet can also make them fail, and in fact, on low power units, are much less likely to fail due to heat, though extreme stress as in using max power levels such like a hill climb wherein speed is below 50% of maximum for several minutes, can do it.

 

[mattgod69]

Hi all...

By way of an update, Fazua have been great. I contacted them and they picked up the drivepack. The replacement arrived this morning and it appears to be a new unit. Very good communication and service from Fazua which has in fairness been my experience in a very beginning with them.

This does give me the confidence to invest further in the company and tends to get another bike the same system on it..

If anyone has any questions, feel free to ask.

Matt

 

[Russellc]

After reading the before comments on Fazua control boards I would comment that I have never found a source for any battery or motor boards. Any problem with a battery or motor requires the replacement of the full unit associated with the fault. I will also add that the first model of battery the 250 is prone to problems. The 250X is a worthwhile upgrade with also more control flexibility