How to Diagnose a Failed Relay In Your Car, Truck or SUV
https://youtube.com/watch?v=F5qTf15PKcI
In this video, we'' re mosting likely to be discussing
just how to identify a malfunctioning relay. A great deal of lorries are different, but a lot of
of the time you locate the relays right where the merges are. So, these big boxes, these are relays. These smaller ones are relays likewise, and afterwards
these are merges, also these are integrates. So, right here is a typical four-prong relay, and
on the side of it, a lot of them have a little trick that explains the electrical wiring diagram for the
relay, and the little pins are numbered on the bottom. And this photo stands for just how this relay
jobs. So, these two terminals stand for 86 and 30,
and there is battery favorable on those terminals all the time. And after that the other 2 terminals, this incurable
stands for 87 and this terminal right here stands for 85. We'' ll talk extra about the numbers later on. We'' re utilizing a horn circuit since it'' s really easy. It'' s easy to comprehend. What we have is we have the horn grounded on this side.When you in fact press the switch, that closes the circuit to ensure that you get
the ground on this side of the relay. That is going to trigger this electromagnet and it ' s mosting likely to move this bar over, and then you ' re going to have battery favorable undergoing the relay.
It ' s mosting likely to drop right here via a fuse and then it ' ll turn on the horn'. So, why do we have a relay? The reason is because you have a high amperage circuit, so it takes a lot of amperage to get the horn to work, and after that you have it undergo a fuse.
And if you had a switch, allow ' s state you just wired the horn right
right into the button of the horn, you'' re mosting likely to have a great deal of amperage experiencing the horn button and it'' s going to stress out a lot faster.So the relay is going to prevent that button from stressing out.
The relay could stress out in time, although they ' re made for this.
They'' re made to have a whole lot of amperage go through them, and after that you'' re mosting likely to have the lower amperage circuit for the button. It doesn'' t take a great deal of amps to get the relay to click, which will certainly make that work, which'' s why you have a relay. Below is a relay with the cover off. You can see the windings for the electromagnet, and this is the bar right here.So, if you pulled the cover off and had this linked and you pushed on that, that would certainly turn on that bar right there, which'' s. just how it works. So, for the thing that you ' re
searching for that ' s. not functioning, we ' re inspecting out the horn circuit,'that ' s the relay for the horn circuit. So, quick and very easy means to examine the relay,. see if'it ' s also working with the switch side is have someone push the horn and actually.'really feel the relay and see if it ' s clicking.
And we can in fact hear it clicking
there. and you ' d be able to feel it too.So, we understand this side of the relay is functioning. when we press the switch.
The relay is clicking, so we understand this side.
is actually functioning. So, something is wrong on this side, whether.
there ' s no power right here, whether there ' s bad get in touches with in the relay, the fuse, or the horn,. and even the ground. Now, what if your relay wasn ' t clicking when. you were touching the horn button? Well, something on this side of the circuit
. is not working, whether you wear ' t have battery favorable, whether the relay internals are. damaged, or also a cable on this side, the horn button misbehaves or perhaps the ground side, so. something in that circuit is bad.So, a quick and easy way to examine if this relay. misbehaves, what we can do is discover another among these relays and just match the numbers. up. So, this is 8866, and this matches over. below, 8866.
So, you wouldn ' t want to change it with one. of these, 8567, although the internals are most likely really comparable, it'' s not worth the. threat. So, let ' s switch the relay, placed this set right.
right here. And it'' d be great to examine the circuit of this.
one prior to you did this. So if this was haze lights, ensure your.
fog lights work.And put this in
. And so previously, we were just obtaining a click. Allow'' s see if the horn works. So, that was a quick and simple means to test.
it. Let'' s try one more examination. Below ' s a relay tester. You can check a number of different kinds of.
relays. This can be a four-prong or a five-prong,.
and after that the different configurations. What you do is take the four-prong relay,.
stick it in right here. You have it connected to battery positive and.
negative, and then you struck the test switch. It'' s mosting likely to test the relay ' s electronic devices. And the relay is good. Now, allow'' s examination our relay. At once, it'' s negative right now. Still clicks, but it'' s not making a great contact.
in between the terminals 30 and 87. And you might make use of a relay package where you in fact.
place the relay in the top of it, and after that you have the examinations on the side. When you connect this in, this is where the numbers.
are important.You can see the numbers right there for which. circuit is which.
This is the relay tester we'' re going to use. So, relay is going to enter similar to this, and.
there'' s our number 30 and 87. Then we can take an examination light, and we can.
see if the circuit number 30 is obtaining power. And we are obtaining power there. If we were to ground 85, after that we should hear.
the relay click, and you can just ground it with the test light due to the fact that it'' s a low-voltage.
circuit, and see the relay clicks however the horn is not going off. If we had an excellent relay, and we did the very same.
thing, you'' re going to obtain the horn
to go off.Or you might additionally take an integrated jumper harness,.
and if you jump both terminals, incurable 30 and 87, you'' re going to listen to the horn,.
or at the very least with any luck, you listen to the horn if every little thing else is operating in the circuit,.
then you understand the relay is bad. So, when I turn the relay over, keep in mind that.
the terminals are going to be opposite of what you see. So, I see terminal 30 is right here, which.
is really mosting likely to be the incurable that'' s located right below, right there, and after that.
87 is going to be over here. They go across, the terminals … despite the fact that the.
electrical wiring layouts that we have actually showed you, it shows they'' re beside each various other, they ' re.
not truly alongside each other. That'' s why you reached take note of the.
numbers, so 30 is here, 87 here. So, we'' ll begin with 87 due to the fact that there''
s no. power on 87. Place the jumper harness in there and then placed.
this side in 30 and simply do it quick.And there you go
. So, now you know a bit a lot more on just how. a relay functions and just how to detect it. If you appreciated this video, ensure you subscribe. to our channel, ring that bell, transform on all alerts so you put on ' t miss out on any one of our. video clips.
