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A friend's car key was not working properly, and an electronics repair shop took it to that key. they offered a very high price for the repair and my friend refused and got his key back. Now he brought me the key and asks me to fix it. but before me the crafty person removed some of the components of the switch from the PCB. This is the switch board. Well, you can still see some components being soldered there but no clue.

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If I type PCB number in Google, the same boards appear there. however, I don't have enough experience to determine what these components are and what their value is. Can you help me find these 3 components?

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there are some links for other images

Full resulation

24 pins component datasheet

Another full resulation image

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    \$\begingroup\$ Some form of resistor for 2 and 3, and a capacitor for 1. There is no way of knowing what value they are without measuring them in isolation or finding a schematic. \$\endgroup\$ – Tom Carpenter Sep 3 at 16:47
  • \$\begingroup\$ "crafty person"... if you look, there is still some fillets so they were probably knocked off \$\endgroup\$ – JonRB Sep 3 at 16:53
  • \$\begingroup\$ They look like parts for the matching network for the PCB antenna. It will not be easy to find the values. \$\endgroup\$ – Spehro Pefhany Sep 3 at 17:04
  • \$\begingroup\$ Even if you knew what types of components would need to be there and you would put them there, in my opinion you still have a very high chance that the key still would not work. Almost all "intelligence" is inside the chip. Either that chip needs to be re-programmed (maybe that's not even possible) or replaced (and then it needs to be programmed as well). My guess is that the chance that you can repair this is zero. Your friend will have to bite the bullet and pay dearly for a new card probably from the car dealer. \$\endgroup\$ – Bimpelrekkie Sep 3 at 19:22
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They seem to be connected to the antenna connection (pins 23 and 24); looking at the datasheet, my best guess would be that 1 is a capacitor between V and ground, 2 is an inductor, and 3 is an antenna. Have a look for yourself to see if that is correct; it shouldn't be all that difficult to reverse-engineer looking at figure 7-3 on page 9 of the datasheet.

The values I can't tell, but they probably used the suggestions in the datasheet.

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