SUV Power Liftgate Wont Open Bad Switch or Latch How to Find Out

Here we have a GMC Acadia and the liftgate is stuck, I can open it, that's what we're gonna go over in this video. Now, this would also be the same as on a Traverse, an Uplander, and an Enclave. So, when I go to use the remote and I push the button, nothing happens. And if I hit the unlock button, all the other doors work. Even if I come back here to the button, button doesn't work right here either. All right, so nothing's working from the outside, we're gonna have to go from inside. Now, I put the seats down. If there's anything in the back, you're gonna wanna move it out of the way. Now, there's no release handle or anything on the back here but there is a little plug right here. Just take a straight blade screwdriver, just try to get behind that plug, pop that off. Now, if you take that same straight blade screwdriver and slide it in here, there is a release, it's actually kind of hard to find. To find the release, I actually used a borescope to get in here. And just take this screwdriver, slide it right there. That's what I'm trying to push. And there we go. Popped it up.

So, that's one way you can get it open, which is good. We got it open. But the second I close it, it's not gonna work again, even this switch right here, if I push that button, it doesn't work. So, we need to figure out what's wrong with this, why it's not opening. Before we go any further, the best thing to do is check the fuses. There's a couple fuses you need to check. Underneath the instrument panel on passenger side, if you pull this panel down, there's a little key and it's kind of difficult to get to, but you're going to look for the DSPLY fuse, it's a 15 amp fuse. So, you can have a test light and hook the other end to a ground and then go underneath and test for the fuses. So, it's this fuse right here. Just check both sides with the test light. And we have power on both sides, so that's good. And then also under the hood, there's a fuse box, you wanna check this 30 amp fuse power liftgate. It's right here. Now this one, you don't test with a test light, you pretty much have to look down in the little window and see if you see that it's good. You could always switch it with another 30 amp fuse that you know is good. And the same, if you didn't have a test light with the other fuse, you could pull the fuse out and just take a look at it and just make sure it looks good.

All right, so our fuses are good. So, the next step, we're gonna take this panel off and get to the source and see if we can figure out what's going on. There's a couple clips in the back that I have to take off, take off this handle, and there should be some screws under there. Now, with the connector right here, what you could do is test these two wires, you're gonna look at the thicker wires. Those ones are gonna activate the actuator, the other ones are just signal wires. So, if you can get a test light on those two wires, and try to plug this back in, test those wires when you're touching the switch. Now, that would work if one of the switches wasn't working. If when you were on the inside, you hit the inside switch and you check that, switch wasn't working or the outside switch, but in our case, all the switches aren't working. So, it's not just gonna be that. And if you had power and ground there, then your latch is gonna be bad.

Another thing you can test the switches, a lot of times these switches get dirt and debris in them and they stop working. Pull the switch out, you can take a meter, put it on ohms, we wanna check to make sure the wires going through the switch and then switch itself are working. So, what the meter is gonna do is send a small amount of voltage down one wire. And then when you push the switch, it's gonna check it with the other wire, you can double-check your meter. Just make sure it does that, I can make it make a noise. So, I'm gonna put one hand on one side of the switch and you just wanna lightly touch it. You don't wanna force it into the terminal. Just like that, and then touch the switch. And the switch is good. So, you can do that with this switch and you can do that with the switch on the outside of the car.

In our instance, everything under this panel looks okay, we didn't have any problems. Now, if you were checking this out and you happen to have a high powered scan tool, scan tool that can read other modules, you would wanna start with this before you even pull this cover off and see if you have any codes in the system, check the liftgate module and see what's going on with that. So, we scan tested the vehicle and found in the liftgate module, there's no codes related to the liftgate not opening. So, there was no codes in the system for the liftgate module. But there is a section in here where it shows the history of why the liftgate failed and where to look for. So, it'll give you a direction where to go.

So, we can see last open failed data, and then here you have to select everything here. But this will give you some idea of why the liftgate wouldn't open, oops, and then we hit confirm and we can go through, and it'll tell you yes, that's why it failed. So, these are all no and then I get to go to the next one, inactive, no, no, no. No, no, no, inactive. Inactive, no. Okay, no, no. And vehicle in park. Yes. So, the reason why this liftgate failed was because the computer that controls the liftgate, the liftgate module doesn't know that the vehicle is in park. So, the reason why the liftgate module is not seeing that the transmission is in park, we recently rebuilt this transmission and put a new transmission control module in it. And the module has to be programmed. Until that module is programmed, it's not gonna send the signal to this module. So, once that's fixed, everything should be working fine.

I tried to show you as much as I could without using the scan tool first. There's a lot of things you can test, you can test the latch, some of the buttons and some of the other things. Unfortunately, there's a lot of computers involved in a lot of these vehicles and there was no other way for us to test it other than to use the scan tool to figure out exactly what was wrong with the vehicle. If you enjoyed this video, make sure you subscribe to our channel. Please ring that bell and turn on all notifications so you don't miss any of our videos.

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