Understanding Washer Control Boards

 All right. With that said, my friends, let's go ahead and move on to the major circuits over here. So the circuit boards, actually, I should say, right? There's, there's three major circuit boards that we're gonna be concerned with regarding, um, regarding these schematics. And what's nice about the diagrams that, that GE has put out there for you is that they actually have, uh, the boards on the diagrams, and they show you the connectors of the components that are attached to, to those boards.

So the first one we're gonna talk about is gonna be, of course, the main control board. So that's that big one right there that you see. And if I go back, you notice that the main control boards f- main control board fits right in that square box, so it makes it nice and easy for us to see. The next board that we're gonna discuss is, of course, the inverter board, and we cannot forget about the user interface board.

So at a high level, let's talk a little bit about what these boards do just so you have a general understanding, but of course, we're gonna go into more detail later on So the main control board's primary function is, of course, to control all major components, and one very important characteristic, okay, is that it does supply 120 volts AC to the inverter.

I promise you, later on, I'm gonna show you exactly where that voltage comes from on the board and how to find it on the schematic. But I just want you to know right now that the board will supply, the main board will supply 120 volts AC to the inverter. And the reason why that's important is because if you don't have that 120 volts AC going into the inverter board, then there's no way the motor can ever run.

All right? So we'll leave it at that. I'll give you the details later, but I just want you to kind of keep that... plant that seed in your mind, and then we'll, we'll let it grow a little bit later on. All right? So what is the, uh, uh, what about communication, right? The, the main control board is also gonna communicate with both the inverter and the user interface board, and it's gonna use DC for that.

Again, we'll go into the details. Now, the inverter board is gonna be what drives the washer motor, and the way it does that is that it converts the 120 volts AC into a variable DC voltage. You're not gonna be able to test that DC voltage, but you are going to be able to test the 120 volts AC, which is why it's very important that you know on the schematic diagram where to find that connector, and then obviously put that information to use so that you can actually measure it.

Now, the user interface board is the one that provides the touch commands from the user, right? So if I turn the jog dial to select a different, um, a different cycle, or if I wanna add time or, uh, change the temperature of the water, things like that, those are all commands that are coming from the user interface, and they're coming via DC, um, signals to the main control board.

Now, the very important thing that you need to understand about this board is that it does receive 13.5 volts DC from the main, and the reason why that is so important is because if you come across a service call where you have a dead user interface, so you go in there, the, the touch display is completely shot, right, you can't do anything, well, something very easy that you can do is measure 13.5 volts DC coming from the main control board, and if there's no voltage coming from the main, the problem is not the UI, it is the main control board.

So again, I get a lot of technicians that say, "Hey, I, th- I had a dead display. I swapped it out. I even changed it twice 'cause I thought the first part was defective, and it's still not working." Well, it's not the user interface. It's probably your, uh, main board that is not supplying voltage. "Did you check it?"

"No." Well, there you go. There, there's your problem right there. So we wanna help you avoid that kind of a situation.