These must be the CH Pedals, not the Pro Pedals?
I have the old CH Pedals that you can no longer get, they are about 10 years old and work just fine outside of a little spiking.
Make sure the "CAR/Plane" switch is on "Plane" . I may not have the exact words printed on the pedal, but you will find a small switch. In Car mode, it will act as two different axises, and in Plane mode, it acts like rudders and one axis.
Next check if it's a calibration problem. I think I had this once. Recalibrate in windows, then recalibrate in AH.
If that isn't it, you may want to look for broken wires. If it just quit, I bet you will find something is broke. First check the obvious, and work your way to the unlikely.
1. Plug, is it plugged in correctly?
2. Where the cable connects to the plug, wiggle it to see if you get a responce.
3. Check for kinks in the cable.
4. Where the cable enters the pedals.
5. At the CAR/Plane switch. Move this back an forth to see if this help.
Good Luck,
Gunner