[GORDON HUMMEL]

There has been a lot of discussions on this board in the past with should prove helpful. I think Newell has the valve w/solenoid/coil included +/- $125 + Freight. I think they were originally produced by AFCO for HWH as on OEM part. While your solenoids could have failed, make sure you are getting power to the solenoid.

On my coach, the tag axle exhaust ONLY gets power from the tag switch OR master leveling switch WITH the leveling & ignition switch on.
The individual drive axle up/down switch's do NOT exhaust the tag axle; they do raise it (the tag), but only if the ignitions switch is in the on position (which activates the main tag solenoid)