It will be a few days before I can post a picture. Thanks. The latch does not use a key at all. We have a 2015 24R. The latch is like all of the other compartment doors, except it doesn't lock with a key. Up until now, I just pulled the black handle and it opened. Now it won't open.
Had one of my latches "hang" - not the propane door, but similar latch except for the lock I believe. With the propane door I think you can reach in from the bottom - the propane compartment on our 2012 has no floor. If you can reach up to the latch you can push the latch dog in and release the door. Take a look at your other compartment latches to see what I'm trying to say. Once you get the door open you can remove and replace or repair the latch. Mine was the latch on the rear door to the "basement". I was able to release the latch from the large side door to the basement. I disassembled and repaired the latch.
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JLeising
2012 Solera "S"
Calif SF Bay Area
Like JLeising stated you can get into it from underneath as it is not inside a compartment, Propane doors are not allowed to have locks on them for fire code reasons. So it must be a problem with the latch needing adjustment. Good Luck.
Not sure of your door / latch type or setup, but sometimes pushing on the door while trying to operate the latch will work. If the setup is too tight, the latch will bind, and by pushing on the door you get the extra clearance for the latch to operate.
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2015.5 GMC 3500HD SLT SRW CC Z71 D/A