How to Test a 3, 4 or 5 Pin Relay - With or Without a Diagram

Рет қаралды 1,697,716

Күн бұрын

Here is a video on how you can test a Relay with or without a diagram. I cover 3.4 and 5 pin relays and all you need is a 12v source, a multimeter and a test light.
Multimeter Used in Video: amzn.to/2bngr5q
Test Light Used in the Video: amzn.to/2aRI2fJ
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Please Consider Supporting My Channel at : / rnwdue to factors beyond the control of Ratchetsand Wrenches, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. Ratchetsand Wrenches assumes no liability for any property or personal damage that may arise from doing a repair on your vehicle after watching any of my repair video's. Due to factors beyond the control of Ratchetsand Wrenches, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Again Any injury, damage or loss that may result from improper use of tools, equipment, or the information contained in this video is the sole responsibility of the user and not Ratchetsand Wrenches.

Пікірлер: 602

@bradical8198 7 ай бұрын

9 years later and this is still the best explanation on youtube

@DavidLorellHoskins 8 жыл бұрын

This was an incredibly helpful video. Your diagrams, explanations, and the stability/positioning of the camera all made this so simple to understand. Thank you

@KevinIndreland 7 жыл бұрын

You're a genius....your videos are always a big help and you spell everything out for us. Thanks a million!

@Hoboappalachia 5 жыл бұрын

This is the best video on relays and testing I have found on KZfaq so far. Thank you! Keep it up.

@hubertwilliams6509 7 жыл бұрын

I just have to say this.. You are a huge inspiration .. You gave me so much confidence and knowledge.. My 2003 Expedition started with a check charging system late February since then .. I've install new alternator, alternator wiring harness, 2 idle pulleys, removed and cleaned tension pulley, checked all my fuses and relays installed new engine belt ..today I got my truck running again and the reason why it did not start was one of the cables going to the fuse box was disconneted

@mbryant107 5 жыл бұрын

This is an amazing video! I had NO IDEA exactly what relays did, what made them good or bad. It was just something you replaced and hoped you got it right! Thank you so much for drawing this out CRYSTAL CLEAR for me! This is amazing!

@speway 4 жыл бұрын

Incredibly detailed tutorial. Absolute love it! The only thing I would add is a brief description on what constitutes a ground. Thanks for your positive contribution to the KZfaq community.

@actualsurfer 10 ай бұрын

We are not yet completely sure...there is one more test, With the 85/86 energized and 87 confirmed "hot", you now need to put that test light back on 87a to see if it is also "hot". Because of your tutorial, thank you, I was able to diagnose my relay as bad. In my case BOTH the 87 and 87a are hot with the relay engaged. Causing all kinds of problems for my motorcycle. I tested it as Good but always traced the problem back to the relay. Did some more playing around with it and discovered my issue. Thank you very much for taking the time to make this video.

@JDnBeastlet 5 жыл бұрын

Thank you for this easy to follow instructional video. I used it to test a relay - something I have never done before - and I found it failed the 4th step (the grounded test light did not come on when the relay was energized and powered). Great job!

@willb5240 Жыл бұрын

Thank you! Out of the many videos on testing relays, yours is the only one I could find for those of us who have a relay that has no diagram or numbers at all. Much appreciated.

@rent2ownnz 8 жыл бұрын

Thanks man.... been a long time since I diagnosed auto electrics a bit rusty. told me exactly what my brain had forgotten in 2 mins flat! good stuff.... Fixed my wiring issue and all running again, but had to eliminate 4 relays to move forward! cheers again!

@Angeldenis1987 8 жыл бұрын

I was just watching to learn about relays. I don't need to check any right now, but now I wanna kust go grab a relay from my car and practice. :) . Nice Video.

@joecain88 12 күн бұрын

Hands down best explanation I've seen anywhere

@rplogix 7 жыл бұрын

Hi, your videos and explanations are very clear and helpful for every one. Keep on your great work. I had a car starter that won't start so before I dismantle my ignition switch I will run your tests. Thanks a bunch!

@joeh2253 2 жыл бұрын

I just saw this video and it's fantastic. I've watched many testing of relay videos on You Tube and this is the best. I have a 5 pin relay that i needed to test and i didn't know what i was doing, now, i feel comfortable that i will get the correct readings. I will now be able to go to the next stip in getting my John Deere Gator working.

@TurboJohn74 9 жыл бұрын

I went to tech school for everything a/c, d/c and digital... but fifteen years later not using that knowledge had me lost helping my father with his truck. Your video was very easy to follow, and lit up the ol' brain again. Thank you so much!

@tamerasj 7 жыл бұрын

I absolutely love and appreciate hands on how to videos! Trying to read a manual and focus on tiny pins or such...........whew, thank you sir for easy to understand info!

@mixedlife1691 Жыл бұрын

I love how detailed you have made this video! Thank you for taking the time to make this video for all of us that are trying to learn this kind of stuff! The only thing i have not been able to put 2 and 2 together on is when you are grounding as you are testing with the light what exactly are you grounding on? This is probably the simplest answer ever but chaos has had my brain scrambled so please enlighten me.

@sammacnab3514 4 жыл бұрын

I really like this guy ! I was having problems with my ac compressor. I followed his instructions and found the AC clutch relay was bad. Thanks so much for posting this ! You're a great teacher !

@brians4377 8 жыл бұрын

Excellent job! Thank goodness for KZfaq and those that take the time to help others. You saved me a big headache and cash. Thank you!

@vector226 6 жыл бұрын

I've watched a lot of your videos and have to say, they are the best and most detailed videos I've seen. I feel confident to tackle the job after learning from you. Thanks for your hard work to get these videos out to people who want to learn how to do it themselves.

@kellypeterson3660 2 жыл бұрын

Fixed my mercedes using this video. Had 74 ohms on 85 and 86. Relays opened and closed just fine. When 85 and 86 were powered and circuit closed, 30 and 87 had erratic ohms from .05 to 34.00. Tested 5 relays and that was the only relay with that problem. Replaced and now cooling fan comes on. Great video.

@papatorr3669 6 жыл бұрын

Just want you to know that you are a God send, Thank you so much. Your channel is my favorite in the DIY Car category. You've helped my son as well who is in the Air Force and is keeping an 88 Dodge Shelby Daytona on the road. I bought a fixer upper 96 Camry 2200 which started right up, but now cranks no start. Simple, thorough, humble, professional, educational, useful, effective...OK I'll stop. Keep up the good work. More technical is more better ; ) ! May not get as many hits, but the ones that do appreciate it more. Harbor Freight free meter?

@geomod6850 2 жыл бұрын

Thank you. These videos are priceless in helping us keep our old vehicles on the road in these difficult times. Much appreciated sir. Good on you.

@TheShady80 5 жыл бұрын

Excellent Video and VERY informative !!! in no way "over kill"..... thank you so much for taking the time to explain every detail so thoroughly...Really appreciated !!

@robertovermier6200 7 жыл бұрын

Great video on testing the three relay types. Came in handy when trying to determine which of two relays were faulty.

@davidpettengill914 2 жыл бұрын

Great video. Your explanation of how a relays works is spot on. Very easy to understand.

@alexandergonzalez2232 7 жыл бұрын

Awesome learning from you the big concepts of integration and the detail points and patterns, it enhances my understanding, thank you!

@kellykemp9336 3 жыл бұрын

Fabulous, great information. I didn't know 'come here from sickem' before viewing. I couldn't even use an Ohm meter and was able to conduct all the tests following your expert instruction. Thank you for your time and Service.

@lakaidude99 6 жыл бұрын

This is a great video. I'm pretty handy with a multimeter, however I've never been able to figure out testing relays. He makes it perfectly clear with full explanations for each step. I used a 12v jump box, my multimeter, spare wire/connectors, and made a phone charger adaptor that usually goes into a 12v cigarette lighter port in a car work as my tester (it has a small red light on it so I could tell that it worked). All in all it took less than 10 minutes to watch, setup, and go step by step to confirm that my 5 point fuel pump relay is in working order. 2 thumbs up, great video!

@Dragon-Slay3r Жыл бұрын

Lol

@dentonscott6967 2 жыл бұрын

You are an excellent Teacher. I am glad I found your channel. Your information is gold!!!

@passingasgarage2375 Жыл бұрын

Soooo, I have a Lotus Esprit V8 and was having some CEL codes and am trying to get to the root of the issue. I had a host of CEL codes related to the Heater circuit on the O2 sensors. I just replaced all 4 O2 sensors, as there are reasonable in price and easy enough to get at. The codes reappeared and so I thought.....after looking at the Fuses and Relays there was a relay for the O2 heater circuit. I pulled the relay and started to order a few relays.....and said let's check it out on KZfaq and here I am. Your video made sense and was informative and I tested the relay that it worked, and that the resistance was good........sure enough clicking away strongly and the resistance was about 76.4, so within your prescribed range. I might have to test a cold start on the relay plug in and see if pin 30 is getting power at start. I would think it should when cold to heat up the O2 sensor. Thanks Again

@motoprophet3981 8 жыл бұрын

Great video. I have a Lincoln LS that would not run. The relays all had good ohm readings and would click when tested. It was the last step that tested the pulled voltage, that revealed the two bad ones. Thanks.

@davidsantiago3360 6 жыл бұрын

Thank you. This is by far the best video explaining relays out in youtube

@tobydufrene1880 3 жыл бұрын

Im having trouble with my 2018 jeep Cherokee. Your video will definitely help me when checking the relays. thanks for sharing the knowledge👍

@jd5787 5 жыл бұрын

Thanks, I have a pair of relays in a wine fridge that may be problematic, I think your video did a good job at explaining how to troubleshoot these things! Thanks

@lspalla65 8 жыл бұрын

Thank you this was very helpful, the only thing I didn't have was a test light when I did your test. don't know how important this is to the test, but everything I did do showed the circuits to be working correctly.

@vincentesolon2210 5 жыл бұрын

I really like you well informed and detailed videos. I currently also have a 1995 Toyota Camry with a cranks but not start weekly. I will have to look at the nss . Really thank you a lot for your many 1995 Camry videos.

@edmundochaparro-barriguete1215 5 жыл бұрын

You are the man with the plan. Excellent video. Thank you so much. You really know your field.

@samuelparra1510 9 жыл бұрын

Thanks for explaining how to test relays and demonstrating how they work. I really do appreciate it. I'll be looking forward to viewing more of your videos.

@myRatchets 9 жыл бұрын

Samuel Parra Glad to hear you liked it, thanks for commenting, cheers.

@lukemartin7029 9 жыл бұрын

This is the best video I've found on relay explanation. Thanks for posting.

@myRatchets 9 жыл бұрын

Luke Martin It got a bit long but alot of info in there for people with patience. Thanks for watching, cheers.

@frigerzoid 9 жыл бұрын

Luke Martin Agreed!, great demo and tutorial.

@commonman80 7 жыл бұрын

Where did you ground The Test Light in the 5 PIN Demo? To The Battery Ground?

@froglegs4910 6 жыл бұрын

He is the best auto professor The EXPLANATION SO CLEAR !

@highlandminger4009 6 жыл бұрын

May be an old upload, but it saved me from buying a fuel pump relay that I didn't need. Thanks

@michaeld9731 Жыл бұрын

Thanks for this information. You have saved me a whole lot of time and I am confident I’ll be able to test the relays for my radiator and a/c cooling fans. 👍

@DerekGHikes 5 жыл бұрын

Thank you for the refresher, great knowledge... been a while since I've done this.

@potterg04 3 жыл бұрын

Great video 👍 I appreciate the facts about relays and how to test them correctly 👍

@daveyusa1884 3 жыл бұрын

this was an even better, maybe the best, explanation, thanks. my relay clicks, resistance goes to 0, but using a light on the terminal does not light up, a bad relay! without that light test, I would have thought it was good, thanks MUCH!

@Damienjking 4 жыл бұрын

Another great video and an outstanding explanation. I would offer just one small word of constructive criticism for future consideration and I hope you receive this in the helpful way its intended. On the paper you layout the pin configuration and the wiring diagram which is very helpful to aid understanding. The one improvement I would recommend would be to make the wiring diagram match the actual pin layout. In other words, both the pin layout and the wiring diagram would have the pin numbers located in exactly the same place. This would make it easier for viewers with little electrical experience. I think this may be why a few people didn't follow what you were saying. Even with that small area for improvement, this is an excellent and thorough video. Thanks for your efforts.

@pablochavez9087 5 жыл бұрын

Awesome stuff. You are great at explaining this. Thank you very much. Learned more here than in auto classes

@erichlg 9 жыл бұрын

Thanks for taking the time to make this video. It's 9pm and I am trying to cure an intermittent crank but no start. I now have confidence the relays are not my problem. On to the next step......

@myRatchets 9 жыл бұрын

Erich Greer Nice, glad to hear it helped you out. Hope you figure out the problem. Come to think of it I might do a video on Crank no start situations.

@safetyalways7788 4 жыл бұрын

My toyota 90987-t2003 relay resistance is 168 ohms. Tested up to 3 relays in my car. All same value. I think the resistance depends on the manufacturer of the relay and the amount of current designed to pass through to them. And all the relay are working well

@WV591 6 жыл бұрын

one of the 3 best auto repair channels on tube. i call it Auto TU

@highlandminger4009 6 жыл бұрын

This may be an old upload , but the section on diagnosing a relay w/o diagram stopped me from buying a fuel pump relay I didn't need...so thank you.

@wolfythelobo 7 жыл бұрын

Excellent explanation... I think I can tackle those relays now Mahalo for your time and effort to share your knowledge.

@bucky2292 4 жыл бұрын

best explanation of testing relays i ever seen ! good job mister !!

@interludo 8 жыл бұрын

So clear. Wish all video tutorials on tube were like this. Thanks.

@ericb5447 3 ай бұрын

What a great teaching video. Thanks for putting in the time on making this for us to learn.

@trevorfrillman8842 7 жыл бұрын

Awesome video! Had a problem with the car but couldn't narrow it down. This helped a ton!

@toantran1 4 жыл бұрын

Thank you for showing me how to test a relay without a diagram. It's great !!!

@joeandgod1 9 жыл бұрын

I agree with spelunkerd, that's the best,easiest, most understandable explanation on diagnosing relays on youtube.

@myRatchets 9 жыл бұрын

joeandgod1 thank you sir for your comment and watching.

@chalkywhyte8585 8 жыл бұрын

Been trying to sort electrical problem on Suzuki quad..Thought a relay was ok because it "clicked". Thanks to your in depth video I now know that it is shot. No power to the light, so I pulled it apart and lo and behold, a blown part on the circuit board. Keep it up, you are good

@myRatchets 8 жыл бұрын

+Chalky Whyte Sweet, very glad to hear the video was helpful. Thanks for your comment. cheers

@raytovar6212 6 жыл бұрын

Thanks this video was so well explained that even i was able to understand an checked my two relays and kept me from wasteing my money.

@philg6757 7 жыл бұрын

Top notch info and explained beautifully.Thank you.

@michaeltempsch5282 9 жыл бұрын

If the relay has a snubber/clamping/free-wheeling/flyback diode in paralell with the coil, then which way you connect 86 and 85 does matter. Connect it the wrong way around and you're likely to kill the diode by over-current. If the diode fails open (most likely) you now have a functioning relay without snubber diode (which upstream electronics might not appeciate). If it fails closed you've got a short across the coil and a non-working relay.

@drummerboysmith968 8 жыл бұрын

+Michael Tempsch I just watched this video and was about to post a similar response and decided to check if anyone else had picked up on his omission of the diode scenario.. Congratulations, sir. I give you a thumbs up. Hope everyone out there reads your comment.

@user-pz6cx8zf2y 5 жыл бұрын

The free wheeling diode is used in electronically driven relays, through the use of a driver transistor. The relay coil is the collector load of the transistor. When the C.P.U sends an energizing command to the driver transistor's base, the collector is practically grounded to the chassis and the relay coil gets energised. The protection diode, is connected in antiparallel way to the coil (i.e. its cathode connected to the battery voltage supply connection of the coil and its anode to the collector connection,that is, to the other terminal of the coil). The diode is therefore in reverse bias, which means that it does not conduct any current when the relay is activated. But when the driving command in the transistor 's base goes off, then the transistor comes in cut off, that is, it acts as an open switch. At that moment, a high spike of reverse polarity develops at the transistor 's collector. The free wheeling diode is forward biased to this spike, it comes in conduction and shorts this pulse to the battery's positive pole. In this way the driver transistor survives for many many operations. In car circuits now, the use of a pulse absorbing resistor is very common for (at least) two reasons. The first one is that the commands to the relays are usually given by hand operated switches. So the possible spike when the switch is off, is effectively absorbed by the resistor. Even if the resistor is not there, the spike will only cause arcing between the switch contacts when the circuit opens, but it will not destroy anything. No transistor there in danger. But the second reason is much more important. The use of protection diode makes the relay coil terminals polarity dependent which is not safe to use in car circuits. The reason is exactly the possibility of power supply reversal during connection which results in damage of the diode, rendering the coil unprotected and therefore a spike generator. In any case, the upstream electronics are not in danger as the energy developing during circuit break is dissipated as arcing within the switch contacts. In the long run, if there is no absorbing resistor or diode, the relevant switch will finally end up having high resistance in its contacts and perhaps will melt them completely. Another important point is that the evaluation of the good (zero ohms) contacts when closing cannot be done by the beeper of the multimeter. This will mislead you. The test needs to be done with the nominal load connected to the relay and then by measuring VOLTAGE across the contacts under test, using Ohm's Law for the evaluation of the test result. The multimeter 's beeper will show you continuity but it cannot give you any measure of current flow at all. This test is the most effective for any power switch...

@Do-iz6qd 2 ай бұрын

@@user-pz6cx8zf2y That is some really useful information, and over my head to be honest. Wish you would make a video, although the chances of you reading this after 5 years ....probably 0.2%....cheers anyway.

@user-pz6cx8zf2y 2 ай бұрын

@@Do-iz6qd I am happy to see that my comment was useful information to you. As regards the testing of power switches in general, the best way is to test them under real conditions (dynamically) instead of using the beeper of a multimeter (because the beeper uses only some milliamperes for testing, which is a negligible amount of current in comparison to the current the switch must deliver to its load)...

@CesNwk10 9 жыл бұрын

by far the best resource for checking relays out there good stuff dude

@green1394 5 жыл бұрын

You are a good teacher my friend,,,,,keep up the good work,,,this world needs people like you,,,MaashaAllah,,,

@mikeyyani 6 жыл бұрын

Te bendigo y gracias por su tiempo en darnos conocimiento para estos problema . Sigue adelante!!!!

@Walkingcamel567 8 жыл бұрын

great tutorial! Now I feel very comfortable testing any relay-Thanks again and keep up the good work.

@hichamouahid4099 9 жыл бұрын

Thank you very much. Indeed this is the best video explaining relays

@1905AdamH 2 жыл бұрын

Utterly awesome vid! So concise and clear! Finally I understand!! Thank you so much!👌😀

@lakshman0680 6 жыл бұрын

Brilliant video. Simple and easy to understand. Awesome. Thanks a ton

@enkisonofanu2301 5 жыл бұрын

Thanks for that, my relay does not have a diagram, but with your help, I can test it. 5 thumbs up.

@stephandelange1776 6 жыл бұрын

Thanks for giving us good front view and explanation video on relays and how to test them, Good Videos really!

@wilmi79 9 жыл бұрын

Best video of its kind, I found it very helpful. Thanks! I'm going to subscribe to this channel. If the other videos are as good as this, I will be very happy.

@myRatchets 8 жыл бұрын

+Michael Williams Welcome aboard, hope you enjoy the video's. cheers

@dragan3290 5 жыл бұрын

Best tutorial on relays ive seen cheers mate!😊

@michaelhorbovetz1820 3 жыл бұрын

I appreciate the step by step instructions you gave on testing relays

@adriandeb2710 8 жыл бұрын

Very helpful video nice and clear to understand.

@1506pinkers 4 жыл бұрын

Excellent. A very clear and comprehensive video. Thank you.

@sonyaadams7721 7 жыл бұрын

Thanks for the great info. You might also want to add a step to check that when the relay is NOT energised, that there is no voltage on pin 87 - if there is it would indicate the relay is stuck on. Thanks again.

@stefanvanvuuren3931 5 жыл бұрын

Thank you so much! That was extremely helpful!❤️

@bonitabonining6047 5 жыл бұрын

your so nice..sir...this video of your's helped so many people to understand.. and to make it of thier own..thank you...😊...im bea from the philippines

@AustinMics 8 жыл бұрын

Great series! Thanks for the info. At 12:53, I think you meant 30 and 87a, to match your diagram. (Normally closed connections)

@kenno251 6 жыл бұрын

Great video, the visualization was a big help to me also, thank you !!!

@jojozepofthejungle2655 5 жыл бұрын

Fantastic, now I know what a relay is. The last video was just pictures, I'm thinking like wtf. Excellent video dude.

@ernieg1415 8 жыл бұрын

thanks for the video. you have helped me with all of my questions and with testing the relays in my cadillac. thank you

@johnnybailey2004 5 жыл бұрын

+Johnny Bailey and

@solopautb6976 5 жыл бұрын

really good information, well and completely explained. nice job!

@alaskanvortex5673 7 жыл бұрын

AWESOME, VERY CLEAR AND PRECISE.

@atanas1964 9 жыл бұрын

Great video! The best I ever seen so far. Simple and very clear explanations. Thank you!

@myRatchets 9 жыл бұрын

Atanas Atanassov Glad you like the video Atanas, cheers!

@brandonaxworth2771 5 жыл бұрын

Great explanation video. Thank you for posting!

@nigelkendall5892 6 жыл бұрын

bit confused about relays until i saw this, this is a great video thanks

@alandmunk3h 5 жыл бұрын

This is totally great. Super clear and I feel smart now too :)

@joakimmattsson694 8 жыл бұрын

Thanks for a very good video! I will show it to my pupils in mecanic workshop

@josephmckoy3427 6 жыл бұрын

Thank you very much for this video! First one that was easy peazy to understand and made sense.

@gregvanderhorn8394 2 жыл бұрын

This is a great video. I seriously mean that. I am in the middle of re-wiring my motorcycle and organizing a rat's nest of wire. This video has helped me greatly

@chrisc6874 7 жыл бұрын

Great video. Like others said, best one on youtube. I think someone else asked this also: I tested all mine and they all clicked except one. As soon as I connected the clips to 85 and 86 (same way as others), it sparked . I took it apart and cant see anything wrong inside. Is it just a bad relay? Thanks

@rplogix 7 жыл бұрын

Yes as mentioned by other, the quality of your videos are amazing. Not only the image quality, but the setup, camera position, you explanations on the board, just great work.

@diegoG928 7 жыл бұрын

Good explanation. Simple. Straight forward.

@guitartricky 3 жыл бұрын

I have a Bosch 5 pin micro-relay which is a little different than the first relay you tes but the diagram is essentially the same. I was able to use the same procedure tp test it. Thank you!

@bjorge970 3 жыл бұрын

"If You dont hear it click toss it no point in going further" one second later "but if you do hear it click you need to go further to make 100 percent sure" hahahah excellent video bro but when i heard that got a lil confused had to play it back couple times to make sure haha

@nooneisahero594 2 жыл бұрын

What does he mean im dumb

@massinissaaouchiche9257 Жыл бұрын

english is my 5 th language but i think it's clear hhh like if you dont hear a click means the relay is bad and you dont have to do any other testing but if you hear a click,you can suspect that is good but need additional test to be 100% sure

@Jeremy-rg3bg Жыл бұрын

@@massinissaaouchiche9257 it's very clear and makes perfect sense...don't let some dummy mix ur head up..your 5th language?..wow!

@TheRealJakeRyanMusic 11 ай бұрын

It makes absolutely makes sense. If anyone got confused over that, you shouldn't be soing electrical work.

@TM-fx5le 6 ай бұрын

@@TheRealJakeRyanMusiccan you please rewrite or delete your comment? 🤦‍♂️

@ImConstantlyConfused 8 жыл бұрын

testing a motorcycle starter solenoid / relay and as soon as power was added it started sparking like mad. not little pops and done but large blue arcs. Couldn't hear it click but nothing changed on the ohmmeter, so guess it's time to order a new one! Thanks for the video, watched a few times to make sure I was testing correctly.

@larrylbaker4927 7 жыл бұрын

Great info ratchets it precise to the point for DIY"ers heres something to take home.on most older hyundai cars make sure the harnesses on and around the motor are not cracked or seperated from connecters

@EmirF121 4 жыл бұрын

Thanks for the tutorial! Is the last test with a test lamp necessary to tell if a relay is good? I have completed first three tests and the relay passed all three.