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Fast Turn Signal Learn How to Fix Hyper Blinkers on Your Car or Truck

Created on: 2020-05-18

Watch this video to find out what fast flashing turn signals mean, and what you can do to fix them!

Hey buddy, your blinker's going kinda fast.

Really? Oh, yeah, I'll have to check that out.

Hey, friends, it's Len here from 1A Auto. Today we got a vehicle in the shop and we're gonna be diagnosing a directional issue. If you need any parts, as always, check us out, 1aauto.com. Thanks.

Now when it comes time to checking your lights, it's a great idea to check them all at the same time. It's also much easier if you have a second person to do it because you're gonna need somebody in there to step on the brake pedal and of course run the directionals. So, with that said, we're gonna grab an extra person and we're gonna get this started.

Okay, let's see what this guy's talking about. Let's go ahead and run the lights. You wanna turn on the running lights? Those look good. We've got our plate lights under there. We've got both running lights on both sides. That's awesome. Let's go ahead and step on the brakes. Both brake lights are working and, of course, our third brake light. This is super important. Go ahead and hit the reverse. Oh yeah, both reverse lights are working. You wanna make sure you have both and not just one. Awesome. Go ahead and turn those off. Thank you. Let's run the directionals. You wanna do a right? All right, so we got our right directional running right here. That looks perfect. You wanna make sure that it's not blinking super fast. Let's try the left side. Yeah, well, there we go. So that's what that guy's talking about right here. Our left side directional in the rear is blinking fast. So we know it's working, it's getting power coming back here so that's great news. The next thing we need to do is figure out why it's blinking fast. Let's go to the front of the vehicle and check it out.

All right, so let's check out what's going on at the front of the vehicle. Let's turn on the headlights. Okay, so we've got both side headlights and, of course, the fog lights turned on at the same time. That's great. Both of those are on. If I look along the side, I can see there's a marker light here. There's a secondary marker light which also looks like it's supposed to be a directional bulb in there. That looks good. We'll come over here. I've got my outside marker light, but this one doesn't seem like it's lighting up right here. So we definitely have a marker bulb out. Let's run our high beams. Oh yeah, high beams are nice and bright. Fog lights turn off like they should at the same time. Perfect. Okay, let's do the right side directional. Yeah, that looks awesome. And the left. Yeah, all right. So we're gonna have to check this out.

All right, so now it's time to get into it. We're just gonna need a couple simple tools. We need to be able to see so you need a flashlight, you need hand protection, of course, and if you have one of these little test lights, that's gonna come in handy. We figured out approximately where the problem is. We know that it's on the left front, right? All the other directionals worked, so we don't necessarily think that it's gonna be a fuse problem or even a relay problem. If for some reason neither of the left side directionals worked, the front or the rear, then we know that we're gonna have to check something a little bit differently here. Or even if none of the directionals worked. If none of the directionals worked, you wanna make sure you check your fuse and, of course, your relay.

Now if one side of your vehicle's directionals were working and the complete opposite side wasn't working at all, more than likely it's gonna be due to this right here, which is called your vehicle's multi-function switch. If it didn't work, there's an issue internally and you need to replace the unit. For our instance, we have one directional out on the left front here. So that's exactly where we're gonna do all of our work. We're gonna locate where the bulb's supposed to be. So if I look right here I can see the head lamp, right? That's not the issue. I'm gonna go a little bit further in and that's where I see the socket for the directional bulb. I'm gonna turn that to the left and get it out of there.

Okay, so we can see the bulb here and we can also see the socket. Let's go ahead and remove the bulb. When you remove the bulb, you're gonna wanna pay attention to those filaments on the inside and they're a little bit hard to see right now through the bulb. But if you can see that they're broken in any way, you need to replace it. It's also a great idea to check to see if it looks like the bulb's discolored in any way. If it looks like it's black in one area or even swollen like it heated up too much, you know you're gonna have to replace it as well.

Now if you look right along here, we have a much clearer view of those filaments that I'm talking about. It has two. That tells me that this is not only a directional but it's also a running light. It has two functions. If either of those is broken, you need to replace the bulb. The next thing we're gonna do is remove the socket form the pigtail. To do that you can squeeze this little tab right here and draw off the socket. Now you want to look into these terminal ends right here. This is where it's gonna make connection to the bulb. You can see those little prongs on the bulb. That's where the current's gonna go through, the electrical current.

Now looking inside here, if you happen to see any corrosion, some blue or green or any funny colors like that, you might be able to just clean it up and you could probably get away with it for awhile. If any of the prongs are broken or misshaped in any way, you're gonna wanna replace this socket. Another good place to look is on the backside. This is the area where the harness is gonna go into. If either of those prongs are broken or damaged or even like I said corroded, you're gonna need to take care of that as well. Let's go ahead and set this aside. And now we're gonna take a look right at the wiring directly.

So I've got the wiring harness here and you can see where the connector is. This is the pigtail aspect of it. If you look right inside there you can see little metal connectors. If they're rusted, or corroded, or discolored in any way, you're gonna either need to clean 'em or, of course, replace this pigtail right here. This one actually looks really good and I can see the rubber seal down along the bottom side there. If it looks like it's missing, that's gonna obviously cause an issue because moisture can get inside there and it's gonna wreak havoc on the whole electrical system. This one looks great so we can move along to testing for power.

Okay, so the next thing we need to do is go ahead and put the key in the on position. The vehicle doesn't necessarily have to be running. Go ahead and put on your running lights and go ahead and put on your left directional. And now we're gonna go back to the front of the vehicle and we'll continue testing.

Now it's gonna be time to test for power up at the front here. To do that, we're gonna use this test light like I said before and we're gonna ground this out right to the negative battery terminal. You can also ground it out to maybe an engine mount or something like that or the frame. I'm gonna start all the way over on the left and let's see if this lights up. Okay. So I have nothing lighting up. That could either be a ground or it could also be an issue. Let's keep moving. This is a nice solid light. That's telling me that that's for the running lights and it's lighting up perfectly and it's definitely not fading in and out. That looks great. Let's move along. All right, here we go. So now I've got this one blinking. That's telling me that this is for the directional and it's also telling me that the directional has power. With that said, this one having power like it's supposed to, this one having power like it's also supposed to, and this one not having anything, that tells me that this should be ground.

All right, so that's how to do it with the test light. Let's set that aside. Now we're gonna go ahead try it with this multi-meter, which is also available at 1aauto.com by the way. I'm gonna set this right over there to the 20 volts. All right. Set it down. I'm just gonna test it. Gonna go right on the negative with the black, right on the positive with the red, and we're gonna test this battery. Looks like I'm about a little bit below 12 volts, the battery's a little low, could use a charge, but there's definitely something there.

The next thing we're gonna do is take our negative lead and we're going to go right to the negative terminal on the battery. Now we're just gonna start testing this down here. I'm gonna start with the one that I believe was the ground. I should have no voltage. That's perfect. I'm gonna move on over. This is the one for the running lights. It looks like we're sitting at just under that 12 volts, which is the same as what the battery voltage was. That's good. That means we're getting power to the running lights. Let's move right along over here. And we can see this is fluctuating which is great. The reason why it looks all messed up like that basically is just because it's blinking so fast the voltage is changing too fast for the multi-meter to keep up with. But we can definitely tell that we do have some voltage going there and it looks pretty decent.

So now that we know we have power on both those terminals like we know we should, we need to make sure we have ground as well because it's not gonna work if it doesn't have ground. Continuing with the multi-meter set to the 20 volts here, we're gonna put our positive right on the positive battery terminal, just like that. Now we're gonna be testing for ground with this one right here. I'm gonna go right to that wire that we were believing that was the ground. And if this shows that we've got voltage running through the system, we know that we've got ground. That looks great.

Now that we've looked for voltage and ground and we know that we're doing all right, let's get our socket back on the pigtail, push it in, listen for a click. We're gonna try this bulb, brand new. All right. I'm gonna go turn those lights off and we'll do them one at a time to make sure they work as they should. Okay, so we've got running lights. Now I'm gonna turn those off. Directional. That looks perfect.

So now we figured out that for this particular application it was a bulb issue. But let's go ahead and assume that for some reason maybe we didn't have power going down here. Let's try to figure that out real quick. Now going with the idea that we don't actually have any power going down to this bulb and socket, we need to start testing a couple other things. There's gonna be a fuse in line, of course. That's gonna make sure that if you have any voltage spikes or anything like that, it's not necessarily gonna burn out any wires, it's gonna burn out the fuse ahead of time. So if something like that was to happen, the fuse is probably gonna be blown. We're gonna go ahead and look inside the fuse box and see if we can find where that fuse is at. There's also something else called a relay that you're gonna wanna check. On this particular vehicle, it's actually inside of the instrument cluster. So I can't actually take it out and show you what it looks like on this one. But there is other relays, so I can kinda give you an idea of what to look for. Let's come right under the hood and we're gonna go to the fuse box.

Can see it located right here, it says relay and fuse. Some vehicles have them under the hood, some vehicles have them inside the car as well. Keep that in mind. If you were to look right along here, you can see all of your fuses, you can see some relays, and of course, some wiring. If you were to look on the backside of this cover, it's gonna give you a little treasure map of things you should look for. We wanna look for one that says turn/hazards. So if I look right down along there, I can see one that says turn/hazards and it's a 15-amp fuse. We're gonna check that one for power.

Now checking for power, we're gonna do it the exact same way as we did before. You can either use that multi-meter or, of course, you can use the test light. So if we look right here, we've got our 15-amp fuse. We're gonna be testing for power on both prongs of that. It's super important to make sure you have power on both sides. To do that we're gonna use our multi-meter. We're gonna set it to voltage and we're gonna go to 20 volts because this is only a 12-volt system, so that should more than cover it. Take your black lead and go to your negative battery terminal and just go ahead and leave it right on there. Now we're gonna go ahead and test both leads like I said. We've got this one right here. It's showing us we've got our full battery voltage here. It is a low battery. We know. We'll test the other side. And that has power as well. That's telling me that this fuse is good. If for some reason I tested one side and it had power, and then I tested the other side and it didn't show me any voltage, then I would know that there's an issue with the fuse. Let's go with an assumption that we believe there is an issue with the fuse now. If you were to look at the backside of your legend box here, you're gonna see this little thing right here. And it's not just a little pretty trinket. It's actually a nice specific tool. You can grab it like that and then this is right where we're gonna grab onto the fuse.

So the next thing that I'm gonna do is remove the key from the vehicle or at least turn off the power before I remove the fuse. Once I've done that, we'll take it out and I'll show you what to test for. All right, so we get the key off. Let's grab that 15-amp fuse with that handy-dandy tool here. We'll lift it right up. So now looking at the fuse you can see right through it. You can see the little conductor that's behind the plastic there and that part's the most important part. If you're looking at it and you can see that it's not actually making a full connection anymore, or you can that the fuse looks like it's black or discolored in any way, more than likely the fuse is no good. If for some reason you can't tell just by looking at it, you can also test it. And I'll show you how to do that with your multi-meter.

The way that we're gonna test this fuse is to actually put our multi-meter on ohms. And that's the thing that looks a little bit like a horseshoe right there upside down. And we're gonna set right it to the 200 because it doesn't really need to be super high, to be honest with you. The next thing that we're gonna do is just take both leads and we're gonna connect it on both sides. You should watch this number drop down to zero. It might take a little while or it might even stop at like 0.2 or something like that because there is gonna be a little bit of resistance. This really doesn't look too bad. Yep, 0.2. Perfect. If you happen to see that it was doing like this when you had them both connected, then you know that the inside right there is no good. So I'm just gonna reconnect it so you can see. Right on there. And it's changing. That's telling me that the voltage is going right through both prongs of this and it's not having any issue communicating. This fuse is great.

Now we're gonna go with the assumption that you found that that fuse is bad. There's gonna be a whole bunch of options for fuses and it might be a little bit confusing. So I just kinda wanna dabble into it and show you a couple options to look for. If you were to come right down here, you're gonna see the fuse that we started with originally. You're gonna see what's known as a Maxi Fuse right there, then you have a mini, and then you have what's known as a micro fuse. As you can tell they go big, small, smaller. Overall, the reason for that is because well, in older vehicles they had a lot less things going on inside, like the computer system and whatnot. And as more and more computer type tings went on, they needed more and more fuses because each thing has to have its own specific fuse in case something, God forbid, happens. So they went to this. But then more and more stuff started getting involved and these fuse boxes can't take up the whole engine compartment so they had to go with something a little bit more like this. It still does a great job, it just doesn't necessarily take up nearly as much space.

Now if we were going with replacing our 15-amp micro fuse here, we would want to obviously match it up. Yeah, this one's blue, and it does actually say 15 right on it. But that's not gonna fit in the hole. Could you try this one? Those prongs do kinda look like they line up a little bit. Maybe it'll work, but it's probably gonna be shooting right up and outta that box and it's not necessarily what's cut out for the vehicle the way that the manufacturer intended it. So would I go with this fuse? Maybe in a pinch, but I'm gonna with a big no.

The next thing we wanna pay attention to is we have a fuse that looks just like it. That's great. But this one right is a different color. And the reason why it's a different color is to let you know visually that it's a different amperage fuse. Now if you were to come right up here to look at this box, this is the box that has the micro fuses in it, it's gonna tell you all the different amperages right along here. And it pretty much is gonna be the same for any type of fuse. So if you have a blue fuse, it doesn't matter if it's a micro, the mini, or even the large ones, it's still gonna be blue. The reason for that is because everybody can kinda determine the blue is 15, the red is 10, and so on and so on, basically. We're not gonna install this one because it's the wrong amperage. If you put in the wrong amperage, you could cause detrimental damage to your engine or even the computer system inside your vehicle. This is super important to make sure you go ahead and you find yourself another 15-amp fuse.

Now that we know we have a matching or corresponding fuse, it's the same color, it's the same amperage, and we know that the conductor inside is good, let's go ahead and pop it inside the vehicle and make sure it works. Brand new 15-amp. We'll slide it in. And we're gonna test it out. That looks like it's working perfectly.

All right, so we checked the fuse. We know we had power there. Like I was saying before, there's something else that you need to look for and that's called a relay. It's gonna look something like this and it's gonna have several prongs along the bottom. It's not necessarily gonna be this particular one, but I wanted to give you something to look at.

Something that's great about relays is they make an audible sound when they get a little bit of power. So when that directional turns on you're gonna hear it. I'm gonna give you a little example of that. I'll plug this one back in where I got it from because that's super important to put things back where you got them from. And now let's give it a listen. Okay, so we can hear it clicking. That means we know that that relay's good.
Awesome. So now that we know the fuse and the relays are good, you're just gonna wanna go ahead and check your vehicle's wiring. Pick one end and start there. All right, so we found our problem. Of course, the next thing you wanna do is make sure you seal this up. You don't want any moisture getting in there. And we're just gonna do one last check of the bulb to make sure that it functions properly. Nice.

Okay, friends, hopefully we found your problem, and hopefully, it wasn't any of this mess. If you like the video, make sure you smash on that like button. While you're at it, go ahead and subscribe and ring the bell, that way you'll be kept up with all of our latest content. If you got something to say, leave it in the comments section below. I'd love to hear it. Thanks.

Thanks for watching. Visit 1aauto.com for quality auto parts shipped to your door, the place for DIY auto repair. And if you enjoyed this video, please click the subscribe button.

Now I just need to figure out where all this goes.


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