About 20 minutes age was sitting in the coach watching TV and got the very acrid smell of an electrical fire. Smoke was coming from the dash panel above the engine gauges. Opened the top cover and found the switch on the air pressure smoking and extremely hot. It is enclosed in plastic/vinyl that was melted and smoking heavily. CO2 extinguisher and wires removed! None of the wiring appears burned, only the sender. There was no warning until the smoke. Thank you Foretravel engineer that designed the easy panel access. Will remove the sender in the AM, look for any other problems and get a picture to post. Autopsy to follow.
Pictures
Looks like the switch shorted out.
Check the wiring diagram and see if that switch is on a protected circuit. Not comforting that it did not blow a fuse or open a circuit breaker.
Wow! Glad you were home when that happened.
Odd to me is that the spade terminals on the wires don't look over-heated, if those are the ones in the background of the first picture.
The part that failed is the relay for the Hadley air horn. The electromagnet switch coil in the relay is now open and burned out. It must have been getting current continuously from the horn switch and was acting like a small resistance heater until I removed the coil wires. The horn switch on the steering wheel was activated long enough for the coil to overheat. The coach is parked and the air pressure was low enough (35-40 psi) for my horn to not make sound so I did not realize the horn switch was being activated buy a book sitting on a sweat shirt, both on the upright steering wheel. The amperage was not enough to open the circuit protection. We are full-time in the coach while we are building a house. We live in Colorado and it still has been cold enough for occasionally needing winter clothing. The drivers seat (and formerly the steering wheel) is/are the go to place for coats and sweat shirts. Never again near the steering wheel switches. The relay is intermittent duty, and not designed to be continuously activated. It was hot enough to melt the insulation and was near the combustion point. The metal burned my hand when I inadvertently touched it. A very valuable lesson learned with only the cost of replacing the Hadley relay.
Great resolution. Thanks for passing it along to us. Lesson learned and shared👍👍 probably powered it down when you removed stuff.
Turning off the controller and inverter when we go to bed does not eliminate all electrical problem points but helps a little. In the above case, probably not. A HD latching relay in place of the salesperson switch might be a good idea also. The entry doorbell button is also a potential hazard point.
Pierce
We are glad you discovered it and you are safe.
We all should share this experience, I've always questioned setting things on the steering wheel. I think some folks even get a cover and make a small table out of the steering wheel when they are parked, set things on it like flower vase.
At least the smart wheel controller didn't cook also
This is a really interesting identification of a potential issue that would pertain to virtually any coach/make/model...just sent to my parents-they have one of those wooden disk tables on the wheel all of the time and this issue has never been considered.
Thankful this didn't turn into a catastrophe!