SOLVED Manatec Garage door opener

[Carl E]

Hello,
I managed to find a corroded ground on my garage door opener. I have more cleanup to do on the board as there are a few via that are nasty looking. The opener actually works, except the red LED which is supposed to flash when the button is pushed. Apparently someone managed to wipe off a component when attempting to open the case. The attached pix shows the red LED with no connection on one end. There is no circuitry on the wire side. I cant imagine what component would be mounted there ( three pads ) unless they used a transistor as a diode. Anyone want to venture a guess? 'This is a FOB for a 40 Mhz garage opener which is obsolete by todays standards. I really don't want to buy a new opener, just a working spare FOB. Thank you

[tautech]

One of those pads is for the antenna connection, nothing to do with the LED.
Instead concentrate on the corrosion about the via before the transistor that drives the diode.

[DavidAlfa]

Put in white vinegar (food vinegar is ok) brush after 5 minutes and leave for another 5 min, all the corrosion will go away.
Rinse with water, ideally distilled water, but tap water will do ok, just rinse later with alcohol and dry with a hair driver or place in the oven at 80°C for 20 min, best with convection fan.

[Carl E]

Thank you.
The missing part is a SOT 23 with the following marks: Z2P with 1G in smaller letters in the corner. I think this is a zener but have no clue what the value is supposed to be. It is in series with the LED so I would imagine I could use something between  3 and 5V.
Any suggestions?

[Microcheap]

This marking code is likely a 5.1V zener

https://assets.nexperia.com/documents/data-sheet/BZX84_SER.pdf

[fzabkar]

http://markingcodes.com/search/c/z2p

FWIW, there are some schematics here ...

Marantec America Corporation FCC Wireless Applications:

https://fccid.io/NKP

[Carl E]

Thank you to all that replied. Yes, the 5.1V zener works. I now have a FOB for the garage.  Querying the FCC website is brilliant.... never thought of it.

[DavidAlfa]

Yeah, the FCC site is a great source of information, almost any electronic device is tested there, often with internal
pictures, sometimes even schematics and datasheets.
Sometimes the pictures have enough resolution to see the markings, or they make macros of them, so it's a lifesaver when your device blew up and all you have is a crater.
Whenever I get a device without readily available docs, that's my first option!