Relays tutorial

[@Cqjones1]

Your video helped me a lot to diagnose my car. Excellent that you explain in layman terms so those of us who do not posses the most basic electrical knowledge could understand. Great work

[@cmacia06]

I'm glad it was helpful! I try to make it simple as possible

[@mseker66]

Awesome video! Very useful and easy to understand. Thanks!

[@SuperFrasman]

Excellent video! Many thanks.

[@logicaliman]

Hello, Christian. Nice video. If you don't mind, I'd like to contribute a little constructive criticism. I realize that you are a college student, and that you are likely thrilled by all the knowledge that you are acquiring in college. That's excellent. You tend to use the phrase "complete the circuit" a little too much in your explanation. Most people are not engineering students, and likely do not have the same familiarity that you have with electrical systems. The standard concept that people need to understand is that of a "closed" or "open" circuit. The also need to know what a "circuit" is. In this case, a circuit is a closed path -- a loop -- in which electricity may flow such as to operate or cause the operation of a device. You are very correct: - in stating that a relay is really an electrically operated switch. - in pointing out that (the majority of) automotive electrical systems operate in twelve volts (12V). But in your overuse of the expression "complete the circuit," it is difficult for the viewer to understand just exactly what is the purpose of your tutorial. Is it to show how a relay works, how to test a relay, or "how to complete circuits" (which most people do not understand)? I believe the purpose of your video is to explain the purpose, use, testing of a relay. (1) How it works. A relay is really a component of two circuits -- in which one controls the other -- and thereby together with user controlled switches -- a user (like a driver of an automobile) can control devices (even without explicit conscious awareness) such as an electric fuel pump or radiator fan or starter motor. What I would point out is that by applying a voltage across poles/terminals 85 and 86, a current in the coil is created which in turn produces the magnetic field you mentioned, and in turn "closes the circuit" between poles/terminals 30 and 87. 30 is the permanent battery (voltage) source in virtually all systems, and 87 is the lead to the device that the relay activates. So, by "closing the circuit" between 30 and 87, power is supplied to the intended device. (2)Testing. So, to test the relay, first a voltage must be applied between terminals 86 and 85. That is what you do with the wires connected to the battery. (a) The second thing that you do in your video is use the multimeter to test for continuity and resistance between terminals 30 and 87. At that point, though, you tend to lose some viewers because some viewers do not exactly know what continuity, resistance, and "complete the circuit" means. What you are really testing for is to see that you have a good "connection between" 30 and 87. This connection should only "happen" IF AND ONLY IF, there is a voltage and current between 86 and 85. The continuity check CONFIRMS that a connection exists, and resistance check checks the quality of the connection (low resistance (like 0 ohms) = good connection). (b) The second test that you perform is with the inexpensive voltage probe light. That tells the tester that indeed, power is transferred from 30 to 87 (by means of a "closed circuit" that includes a path from 30 o 87). To use the test light, it must first be tested, directly with the battery, as you do. It must then be connected to the negative battery terminal (or grounded -- connected to a metal chassis or engine part that is itself directly or indirectly connected to the negative battery terminal) at the alligator clip at the end of the wire. Terminal 30 itself must be connected directly to positive battery pole by means of a wire, as you do. Then, to complete the actual test (which you again refer to as "to complete the circuit"), one has to touch terminal 87 with the tip of the test light. If it lights up, THEN the circuit that includes the path between 30 and 87 is closed and the relay APPEARS to be working. (3) FINAL TESTING. There is ONE VERY IMPORTANT THING that you overlooked. A relay is a switch. It ALSO has to "turn off" devices. Your test ONLY tests for turning ON. What if the relay is stuck on "ON" (a permanently closed circuit)? The tests that you described fail to check for this. Only the clicking sound that you mention near the beginning is any indication that the relay "may" be operating. As part of the tests described in (2), above, the tester should disconnect the voltage source between terminals 85 and 86, and THEN also check that there is NO CONTINUITY (or check for infinite resistance) between terminals 30 and 87, as this is the DESIRED CONDITION when there is no current between 85 and 87. This test can also be done with the test light, as described in (2)(b) above, but with no voltage across 85 and 86. The test light should NOT turn on. (4) The BEST WAY to test the relay is the natural combination of (2) and (3) above. Connect all the wires as you describe in your video, and as described above. But run the test(s) alternatively with voltage connected to 86 -- and then by taking away the voltage. That is PRECISELY HOW a relay works. CONCLUSION in one sentence: the PURPOSE of the test is to test that terminal 30 connects with terminal 87 IF AND ONLY IF a voltage is applied across terminals 85 and 86, and that they do NOT connect under any other circumstances. I hope that you accept this in a positive way and that it helps your subscribers and viewers better understand the concepts that you do. Thank you.

[@cmacia06]

+Logicaliman Thanks for the criticism! It was very well thought out and very well stated. Your definitely correct in saying that i may have over used "closed loop" thinking that people are at a level of that understand. Unfortunately this video was released before i got the hang of editing, and taking video for that matter. This is why I now wait at least a week before releasing videos. It gives me time to review what I really meant to say and who my intended viewers are. Ill take your suggestions and apply them toward my future videos! I wish people had this kind of constructive criticism more often. KZbin would have great videos all over the place. Just to add in case you post comments of this nature in other video, for some reason KZbin spams long comments. It's such as disappointment because you aren't the first person on my channel to get spammed without meaning to. I've had comments with intelligent responses and intriguing information that never get read because I see them months later.

[@SuperEastcoast]

Awesome Job! Nice presentation! Calm and exact, get your self a tripod and keep it going! Thank you!

[@cmacia06]

Ha Ha Thanks! I just purchased one about 2 weeks ago! Glad you liked the video!

[@SuperEastcoast]

From Houston Texas. Your video serve me as a refresher. Again thanks!

[@cmacia06]

Sometimes it's hard to remember those when those pin numbers are. Sweet! Huston. Im in el paso, faaaar west Texas.

[@billybassman21]

Great video. It should be noted that there are normally open and normally closed relays depending on your application. Also there are single pole and multi pole's, as well as single throw and double throw relays.

[@patrickcamilon5880]

liked your vids so far. easy to listen and understand. just saw your "check your relay vid and it was great. was having a problem with my civic, sometimes the fuel pump turned on and sometimes not. so now with your help, i can check my fuel pump relay

[@cmacia06]

Patrick Camilon It happened to my brothers civic and it turned out to be the fuel pump it self on his car. We had our fingers crossed it was the relay but on his, it was the pump. Glad the video was of help and good luck with your civic!

[@patrickcamilon5880]

well here's a little tip when your cvic won't start and you've gone thru all the regular checks, ie grounds, pump, ignition coil, relays etc...Try this......clean out your AIR INTAKE! NO AIR NO IGNITION. SHOOT I CAN'T BELIEVE IT WAS AS EASY AS THIS!

[@cmacia06]

Hahaha. I swear, this happens way more often than I want to admit haha. I always forget to check the simplest things first

[@SteveDeLeon]

Thanks for the video it helped to understand its theory on a relay!

[@mrdannyverma]

Awesome video! Very useful

[@robertocarlosmayta8658]

Good job on this tutorial! Very easy to understand. Do you mind showing us how to test wiring harness on the blower motor.

[@liviudaniel5082]

yeahhhhh ,chris, nice vlog!useful!

[@DJDozyDoh]

Nice video, I have some strange electrical problems with my Ford Focus and will try this to test relays and fuses. By the way what should I look at if abs, emergency break lights are on, and the heater blower, power windows and windshield wipers dont work?.......

[@cmacia06]

you should do a general check of the vehicles wiring to begin and replace and messed up wires. once you have done that, you should make sure all wires that connect to ground are properly seated.

[@DJDozyDoh]

+Christian Macias thx I appreciate it

[@Cqjones1]

keep on doing it bro

[@carltonlowe4112]

Can you do a video installing a kill switch with a relay

[@cmacia06]

+Carlton Lowe when you say use a relay, do you mean to use something like the starter relay to stop the car from starting? Or make a kill switch with our own relay?

[@carltonlowe4112]

+Christian Macias yes a relay to stop the car from starting

[@cmacia06]

Yea definitely.

[@asaamv]

i have a nissan march 2012 and iam having many electrical problems , right now fog light works and headlight works, front wiper but the electrical lock system not working and turn signal not working , and back wiper not working , any idea what do i have to change ? btw turn isgnal is flashing rapidly but no signal is on from the bulb. this means its a problem of the whole electrical system ? not only replacing fuse or relay or bulb will fix it?

[@shellylovingsandiego2101]

Is a zero read when its all hooked up a bad relay?

[@Clod15]

Does it matter, if you put positive on 86 and negative on 85 or is there not a reason to worry about that because it just needs the current to create a magnetic pull?

[@Clod15]

nvm i just got to the part, polarity doesn't matter lol.

[@angelzapien249]

do u know what could cuz my speedometer not work all other gauges work