I am having problem with a logic card. It thinks the subgroup switch is pressed in and therefore won't let the line or mic input pass through. I have tracked the problem down to the logic card. If I put a fully known working logic card in the channel everything works fine. I get 12.7 V on pin 14 of the logic card (Sub-Group Input Switch). When I depress the switch, I get the 17.6V and everything works fine so I know the switch isn't the problem.
On the logic card that isn't working properly, on Pin 14 I am getting 17.6 V no matter what state the Subgroup switch is in. Since this is coming direct to pin 14, I cannot figure out where the problem would be. I should be getting the voltage at the pin no what card is in. What component do I need to look at to track this problem down.
Very, very strange.
