a similar, but different, problem happened to our dryer yesterday...
interestingly, we are two RVs parked on a leased private property, with access to utilities from a former mobile home that has been removed years ago. Along with our other needs for the 50amp outlet for our motorhome, and 30amp outlet for our camper, we also have a 50amp NEMA 14-50 Outlet that provides power to both/either our Nissan LEAF(all battery powered) 240v charging cord, and our 240v clothes dryer.
While neither of these actually have a typical '50amp RV service' 4-wire plug, both are able to make use of the outlet with 'dogbone' type adapters, which create the requirement to 'adapt' from the 240v 4-wire service from the main panel/outlet, to the two differing 240v 3-wire plugs.
The Nissan Leaf Level 2 240v charger and cord use a 3-wire/prong 240v design, and the 'dogbone' adapter simply provides the appropriate 3-wire female outlet to plug into.
The clothes dryer is almost the same 3-wire plug, but the prongs are not the same, which is why it needs it's own 'dogbone' adapter. (some newer dryers use a 4-wire 240v plug/outlet, but that's a discussion for another thread)https://www.amazon.com/gp/product/B07PB5GCTM/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1
I typically keep the Nissan LEAF Level 2 charger cord always plugged in to the 50amp 240v outlet, as the car is used daily, and certainly is used more than the dryer, which is only about once weekly.
When I need the dryer, I simply pull the LEAF adapter/cord from the 50amp Outlet and plug in the dryer's adapter/cord. Easy.
Yesterday, though, when I went to do the laundry, I unplugged the LEAF and plugged in the DRYER.... PPPOOOOOOOPPPPPPP! it immediately POPPED
, though I could not determine exactly 'what' had popped, as the sound seemed to come from the outlet, but the adapter and cord was being plugged in at that time, so I really didn't know for sure.
Now, whenever I hear a 'pop'!, I tend to think that a breaker has tripped, but I tried the dryer anyway, to see - nope, the dryer now would not work. So, off to the main panel I went, but the double-pole breaker had not tripped. o.k., so what next?
I decided then to do a test, without my voltmeter, as I could simply plug the LEAF charger back in, and see if the OUTLET still had power ...... yes, it DID. o.k., so what next?
If the breaker had not tripped, and the other adapter and plug worked, it could only be somewhere between the dryer's adapter, plug, wire to the dryer, or the dryer itself.
Hmmmm.... so I though that the 'weak' point here could be the adapter.
These 'dogbone' adapters are quite beefy, well designed, and since they are of fully molded plastic/rubber there's little to 'go wrong'. There's nothing to 'take apart' and look at, other than the mail prongs on one end, and seeing down into the female end to see the brass connectors on the other. What I noticed was water, water dripping out.
o.k., now we're on to something. Water and electricity 'don't mix', as they say, so I came to a quick conclusion that this 'water' inside the female end of the adapter, probably caused a quick 'short', which caused the 'pop'! sound I heard.
Now, if that's the case, why does the adapter no longer work?
I'm not sure if these adapters have any type of 'protection' in these scenarios, but it might be quite possible that they do have built in 'automatically resetting fuses', but it's possible.
I used a hair dryer to dry out the female end as best as possible, and then retried the connection to the 50amp outlet, and voila!, it worked again. Maybe there's an automatic built-in fuse, maybe not, but it worked again after some time, whether my drying helped out or not, I'm not sure, and maybe it just needed 'time'...to reset!