Many apologies for the confusion
To clarify:
My wife and I both have a Freego Hawk bike and these have identical controllers.
Whilst in use her machine stopped working – i.e. would not respond to pedaling or to rotation of the hand throttle. There was no obvious reason – e.g. smoke, fire, motor run away, etc. etc. - for this failure. All the LEDs on the control panel remained illuminated.
From this I concluded that the controller on her bike was at fault.
As my bike was still working, I took out its controller and replaced it with the faulty unit from her bike.
After this change over my machine also stopped working – i.e. would not respond to pedaling or to rotation of the hand throttle.
This confirmed that the controller on my wife’s bike is faulty.
What caused it to fail is not so clear. It could be: (1) break down of an internal component alone, or (2) possibly in combination with a failure in the connected electrical equipment (motor, wiring etc.)
I think it is most likely to be (1). Are there any tests I can do to establish whether it is (2)?
In the meantime I am going to need a new controller. To simplify the change over, I would prefer this to be as close to the existing unit as possible. Also cheap, as if I get it wrong, can live with the loss!
Grateful if you could help with Internet links to a suitable controller for me.
OK. That's understandable and makes sense. Controllers are pretty reliable. I think that I've only ever seen five faults in controllers in many years of testing and fixing electric bikes.
fault 1.
Battery connected the wrong way round. It often blows the shunt and main capacitor/s, and sometimes blows other components. If you didn't fit a new battery, this fault can't be possible. It's not worth attempting to repair this fault.
fault 2.
Short circuit on the 5v rail blows the 5v regulator. This is easy to repair by replacing the regulator. You can test it by measuring between the red and black wires on the throttle, pedal sensor or motor hall sensors with the controller powered on. You should see 5v. The problem is caused by water getting in the throttle or any of the connectors with 5v on them. Salty water of winter roads is the worst..
fault 3.
Software annihilated. This happens when you get water in a throttle that has battery indicators in it or in any connector that has battery voltage next to 5v. This fault is nearly impossible to test. You can only determine it by a process of elimination and inspection. If you had fault 2, you might have fault 3 as well because they have the same cause. You also get this fault when messing about with connectors when you don't know what your doing. People buy a new throttle with mismatching connectors and then try and get it working by experimentation, connecting each combination of wires. If you connect the battery wire to the 5v, it blows the main CPU and can blow any of the 5v devices on the 5v rail. This fault cannot be repaired.
fault 4.
Blown MOSFET/s. This happens when you draw too much current for too long, like riding your bike too slow with full power. Low speed and high power is very bad for a bike with a hub-motor. This fault is very easy to test. Disconnect the controller and measure the resistance between the battery positive wire and each of the three motor phase (power) wires, then again for the negative battery wire to get six results. Each set of three should be the same as each other and in the range 7K to 14K. This fault is not worth repairing.
fault 5.
Blown transistor that switches on the lights. Some controllers have a lights switch function and a connector that provides the battery voltage to connect the lights too. If you connect lights that draw too much current or get a short circuit in the cable to the lights, it blows the transistor and it can do other consequential damage. In the cases that the controller was still operational, the lights stayed on all the time. It's not easy to test, but you can normally see the burnt transistor on the controller's PCB. You follow the wires from the lights connector to where it's attached to the PCB , and the transistor will most likely be sitting nearby.