Hey everyone, I have built a circuit which includes a PIC. The logic is that if a specific pin gets a logic 1, the output pins will be activated and LED lights will flash. I am controlling the input pin with a magnetic reed switch. It was working great few days ago. However today the output pins are activated even if the reed switch is open. The weird thing is that when I want to check the voltage in the input pin (I am linking one prob to the pin and the other one to the ground) the output pins stop. What can be the issue? I don't know why linking a theoretically infinitive resistance parallel to the circuit cause this stop. Could you please help me? Additional information: I plugged out the switch but it still activates the output pins. I broke the link and it still activates when I touch pin.