Chosen Solution

So, I have a Logitech DFGT wheel that has been working without any problems for a few years now. Today, randomly FFB just stopped working, I tried reconnecting it and etc., but zero response. The power brick works, we tested it. Wheel gets detected by the computer, testing shows that all the buttons work, port for power also works. Tried reinstalling the software, didn’t help. The only problem is FFB. Any ideas where should I start looking?

So, I sold the wheel, quite a few months ago now actually, but only now I remembered to do an update, because maybe, it’ll be useful for someone. The guy I sold it to, found the problem and it was something with the sensor which counts how many times wheel rotates, I’m guessing that’s going to be the optical enconder? It’s a translation, so it might not be accurate, but he said that the problem was that a few traces were broken on the sensor’s board and one of the connectors was moving a bit.

TL:DR; If you have a problem similar to mine and a new power adapter doesn’t help, chances are the problem lies in the optical enconder.

Do you have the ability to measure the voltage while the steering wheel should be powering up? Measuring the power supply voltage unfortunately doesn’t really tell you much, because if there is no current being drawn while the thing is actually defective, it can suggest perfect operation, whereas, when the steering wheel should be powering up and you see the voltage drop significantly, you might be a little wiser.

  1. Measure the terminals at the board upon power up or
  2. Take a ceramic resistor to act as a device that’s causing a current draw (one of those big white square resistors). Next step if previous is ok: measure the current drawn between the supply and the device requesting this current. Take the maximum output as a threshold, anything well below that (and I’m talking milli-amps above or even a full zero here) and you might be looking at a power supply that seems to behave right, but actually isn’t. If that’s true, try to look inside the powersupply and see if there are worn out capacitors

So, an update after a month. I ordered a new power adapter from Aliexpress, instead of doing some more testing. It finally arrived and the wheel is still dead. Checked the voltage on the adapter with a multimeter, that’s seems fine. Chances that it has the same problem as the previous one I guess are small, so most likely it’s something in the inside of the wheel, which is really sad. Thanks for trying to help and I at least learned a few things.