How do you remove the faceplate of a JBL MR 140--I don't have a release key?

Question edited for clarity, proper 'make model (what it is)'.

I can't find a manual, but they have a common theme. Remove the faceplate and press the Reset Button, then clean the contacts both sides with electrical switch cleaner or Isopropyl Alcohol.

https://www.premiumleisure.com/Manuals/nov07/Hydro_Spa_JBL_Stereo.pdf

https://www.rocktheboatmarinestereo.com/specs/MR18.pdf

https://www.google.com/search?q=JBL+marine+MR-15b+manual

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Check the fuse if the fuse is good check if you have pluged the face well

try a wreckers as they salvage a range of radios.

See page 2 of this manual:
http://www.prospecelectronics.com/manuals/JBL%20MR5%20manual.pdf

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dfsd

Because of that moisture it may have fired the lighting connection inside the unit, does it produce and sound?

you can make one to fit where you want

I have looked at several sites and none say that they do so I assume they don't.Also if a player does it normally says on the front.

To get your Sirius ID number from you MR-17 JBL stereo, select the Mode button until it displays "Sirius". Then push and hold the Mode button for a couple seconds and it will chirp and display 3 blank spaces. Enter three zeros, "000" in these 3 spaces. The Zero is the loud button labeled "LD". When you do that, it will display your Sirius ID number. :)

try ebay, or amazon