I'm trying to reverse engineer this circuit so that I can use the buttons with a microcontroller.
The problem is with buttons on the left.
Counting from right to left, above on pin 7, I think that's ground (blue connection.)
I don´t understand the difference between press the upper left button and the lower left button.
I also don't understand the purpose of the resistors since the others buttons don't have resistors.
Are the buttons on the right toggle buttons? Pressing the upper one is the same as press the lower one, right?
EDIT1: The board is from a car, so I suppose it's 5V.
I want to use it with an Arduino. I tried to connect pin 7 to GND from the Arduino, and pin 14 to an INPUT_PULLUP, but no luck, voltage from 14 to 7 is 0.2V instead of 5V.
Schematic from what I understand from buttons on left side (upper and lower)