Worning Horn Problem
 

This is one I have not seen before !!! 1975 P337, when the gear lever is placed in the up posisition the horn goes on and stayes on until you put the lever down. I have disconnected both thottle micro swt's, checked the squat swt, checked left & right main gear micro swt's. Also I am not sure where the control box is located, on my 337B it is located below the radio stack.
Fred N358

Horn Problem
 

I had the same type of problem.

You said you checked the Sqwat switch, but did you check the wiring back up to the sourse of power for sqwat switch. My problem was a bad wire one time and the next time I had the problem, it was right after they put a new seal on nose wheel yoke. The seal was so tight, the nose wheel would not extend all the way and the sqwat switch would not transfer and off went the horn. Raise the nose slowly by having a guy on each boom, pull down real slow until nose wheel drops to open sqwat switch and see how far the yoke drops. Remember airspeed will induce a back preasure on yoke and cause a slight bind in yoke dropping.
good luck, Dale Campbell

Fred
The warning horn box is up in the roof port side centre panel. Just rip down the panel and there should be a silver box with 4 wires and a white connector by it.

This is a dual warning unit and it does both the stall and gear warning.

Did you disconnect the thottle micro switches on the front engine, just aft of the front thottle sw is a white inline connector, if you pull it apart it disconnects both micro switches, handy if you have a DVM as you can check both switches from here and set them up.

With the there should be no power at the brown wire on the warning unit with the selector in the up position.

Also check the white wire from the warning unit and with the thottle switches diconnected, connect a DVM to the white wire and make sure it does not go to ground, if it does the squat switch is faulty or you have a short circuit on the wiring in the engine bays.

Cheers
Pete

Warning Horn
 

Thanks Dale & Pete, I will keep you informed.
Fred N358

Horn
 

Well, the problem went away !!!!! I am sure it will be back.
Thanks again Dale & Pete
Fred N358