CAN Bus Communication Explained (Part 1)

"Where do I start?" That's the question that gets asked the most when it comes to diagnosing CAN Bus issues. This is the first part of a three part series designed to take a real world approach into CAN Bus troubleshooting . In this video we take a step back from the protocols and labscope readings and focus on breaking down these complicated networks into something more manageable.
CAN Bus resistor -- amzn.to/3OIAUWm
CAN Bus Wiring and Protocol Explained (Part 2)- • CAN Bus Wiring and Pro...
CAN Bus Troubleshooting and Diagnosis Explained (Part 3) • CAN Bus Troubleshootin...
#cars #learning #autorepair #diy #fixed

[@SchrodingersBox]

Wow it’s clear you spend a lot of time preparing this. Very well presented! Looking forward to the other parts.

[@GoTechTraining]

Hello, Thank You! It was quite a bit of work to get the flow correct, but it was also a lot of fun to make. ~Ryan

[@rickrogers2649]

Great stuff Ryan. I'm an old retired guy trying not to fall too far out of the loop. Thanks for all your help. Looking forward to the next installments.

[@GoTechTraining]

Hey Rick, Thank you! for supporting the channel and reaching out! I’m working on part 2 now! Stay tuned ! ~Ryan

[@scottnusser6232]

Old fossel here, been shop owner and wrench 45 yrs. Almost turned you off, another freekin egghead I says, but your demeaner kept me watching. Learned alot, thankyou! Nice to see young man with passion for your proffesion! I subscribed! One thing you said is huge and very overlooked. Take the time to thouroughly inspect vehicle. Fixed alot cars in my time with eyeballs, best tool in the box!😅😅

[@GoTechTraining]

Thanks for the support and for reaching out! I 100% agree visual inspections are so important! ~Ryan

[@manueladams5327]

Glorified Map reading- great stuff- Big Thank You!

[@edthompsom9368]

So simple a DIY'er (like me) can follow....thank you!

[@GoTechTraining]

Hey Ed, You're very welcome! This is the way I diagnose CAN in the shop. I'm glad you enjoyed the video! ~Ryan

[@jimyep9971]

Same here. great video.

[@terryharvey8627]

Thanks Ryan for giving us insight on breaking down the house of cards. A deck of 52 is harder to test than a suit of 13.

[@GoTechTraining]

Yes it is Terry! Someone was paying attention! Thanks for watching! ~Ryan

[@raisedbygypsies5171]

Well done Ryan! When you think you know a tricky subject, try to explain it in a concise way so everyone can gain from it. You did this very well! Looking forward to part 2.

[@GoTechTraining]

Thank you! Part 2 coming soon!

[@OR-River-Rat]

Thanks for demystifying a complicated topic. As someone who's worked on data networks for 30 years, I'm impressed with the core principals you shared.

[@samuelgraber6921]

Thanks for Awesome simple video on Can Bus. I'm a young Mechanic starting out and it's hard to diagnose something that you don't understand. And thanks to all the techs in the comments sharing information!

[@euko6876]

Ryan's a phenomenal teacher especially within these systems. Thank you for all your hard work & expertise

[@johnmitchell8925]

Im 62 Retired master auto heavy truck and EVT certified.I own a 2018 chevy cruze, Turbo Direct injected Bought brand new 5 years ago.Its way above my expertise but I'm learning thanks to great teachers like yourself Nobody touches my car but me😁

[@GoTechTraining]

Never stop learning new things! Thanks for watching ! ~Ryan

[@maxdm1583]

Master Auto Tech buying the worst GM car. You must have finished last in your class, haven't learned anything and had no interest in your job. Awesome!

[@connorhutchens7688]

Sell that car now😂😂

[@gasgas2689]

That network at 8:44 reminds me of 1975 when the bank I worked for first joined all 300 branches to a central computer where I worked. Each one of your individual networks was a city or county with several bank branches, and each area connected to a multiplexer which in turn communicated with the central computer. I can understand that ! 😃

[@tedjohnson64]

Phenomenal presentation! Loved the historical to modern progression, and the myriad analogies and real world examples. Now I can finally understand what Pine Hollow Auto Diagnostics and South Main Auto are doing. They zip through the wiring diagrams so quickly, I could never quite follow their logic. It all makes sense now. Cheers!

[@mikechiodetti4482]

Thank you Ryan! Eric O from SMA used to explain how to separate the modules. Ivan from PHAD explained and then separated the modules using his wiring diagram and clip board. In both SMA and PHAD the viewer got to see the vehicle start and run with the problem still further down the line. Also the tech tips for bypassing a module to test the system. ( High, Medium, Low Speed CAN.) You're explaining how to test the systems, what to look for (green crusties, mice bites, etc) and ya, sometimes you do get lucky during a visual test.

[@GoTechTraining]

Hey Mike, Both solid YT channels! I’ll have to check those videos out! Thanks for watching and stay tuned for part 2! ~Ryan

[@geovanybonilla2244]

Thank you for the information, for taking your time and sharing your knowledge with us, it is very helpful. Thank you

[@GoTechTraining]

Hey Geovany, Glad you like the video and we are working on part 2 now, thanks for the kind words! It helps motivate us to keep making videos! ~Ryan

[@whiphaven]

So well explained, even I understood it. Brilliant explanation of how everything works and can be tested. Thank you so much

[@enriquediaz1591]

Thank you so much sr. After watching your video, things are more clear than before for me. I’m still need more to understand the net work but for now it’s more better. God bless you

[@bakryahmed9178]

This is the greatest lesson I have ever seen.

[@eacherenkeka]

Great information Ryan! This system is complicated but if we break it down before we connect the oscilloscope and the multimeter it should be easier. Thank you for the class! This topic is very important for all techs!

[@GoTechTraining]

Hey Keka, I agree 100%, we need to simplify these complicated systems so we can have a fighting chance to diagnose them. Thanks for reaching out and for checking out the video! ~Ryan

[@kevinavery2518]

just to add, these vehicles will do weird things if something isn't communicating, I just got done doing an engine on a 22 gmc sierra 6.2l, i like to run my engines before I put everything back together, make sure i dont have any leaks or noises and such, had the snorkel off maf disconnected, started the truck, no oil pressure on the gauge, truck ran great, no noise's so I knew it had oil pressure went at diagnosing the oil pressure sensor, all tested fine, only code stored u1345 lin bus lost communication with ecm, went down the rabbit hole, looked at my lin bus coms, learnd that the maf is on that, went ahead and put the snorkel back on, plugged in my maf sensor, and boom, oil pressure on the ipc now works, makes no sense to me, but now I know...lol

[@GoTechTraining]

Hey Kevin, Wow! That is crazy, it is almost like it went into a weird default mode because the MAF sensor wasn't talking. Thank you for sharing, information like this can really help someone that may run into a similar problem! ~Ryan

[@shaffere33]

Thoroughly enjoyed the breakdown of networks and ways to diagnose them. Great video

[@GoTechTraining]

Hey Eric, Glad you enjoyed the video! Thanks for watching! Part 2 coming soon! ~Ryan

[@NewLevelAuto]

I learned today that we dont give Ryan crayons and expect him to stay in the lines 😊. But honestly a great job 👏!

[@GoTechTraining]

Hahahaha, Almost as bad as my handwriting lol! 😂

[@jorgemat8080]

Absolutely amazing information. Thank you for taking your time and knowledge and share it with all. 👍

[@GoTechTraining]

Hey Jorge, Of course! Thanks for checking it out ! Glad you liked it ! Part 2 coming soon ! ~Ryan

[@JCWren]

This is a really good video. There's one reason you didn't touch on as to why there are so many busses. Besides trying to isolate a single failure from taking down the entire vehicle, silicon and plastic is still cheaper and lighter than copper wiring. As an example, it's cheaper and easier to run a single power wire and a smaller gauge pair of CAN bus wires to the tail light module than individual wires for the turn signal, brake light, and backup light. Plus the tail light module can self-diagnose lamp failures and report those back. Of course, the downside is that the tail light module is 20x more expensive if you have to replace it, and you'll be lucky if you can still find one 10 years later. This increases the likelihood of the car being declared totaled after an accident, and the vehicle needing to be replaced, which definitely benefits the manufacturer.

[@GoTechTraining]

Great point ! Like window switch’s with three wires and 100 functions! Thanks for reaching out! ~Ryan

[@cpcoark]

This looks like an excellent class. Looking forward to the future parts

[@GoTechTraining]

Hello ww_big_al, Thanks for checking out the new video! Working on class number 2 as I'm typing! ~Ryan

[@venharis2012]

I was a dealership trained ASE master auto tech from 1984 to 1994. After years of low pay and disgust with the way the industry was run, I got out and went back to college. If today you guys are at this level of technology and still working at a dealership or independent shop on a commission basis and still having to deal with the cut throat warranty programs, your nuts and should have your heads examined. There are way easier ways of making money on the clock just waiting around for something to break down. I worked Frac as an E-tech for 8 years. I basically worked 12 hours a day and got paid 16. We sat around and listened to the radio waiting for a call. Some shifts there was no calls. When there was a call we usually got it fixed in 15 minutes and they got back to work. At weatherford they were paying us every two weeks, per diem every two weeks and a monthly $1500 bonus. That's five checks a month... Yearly earnings were $120K to $140K per year. Don't let the auto repair industry short change you fellas. There is a whole world out there that needs your expertise and is willing to pay you good money for it and they won't make you bust your ass for it most of the time...

[@GoTechTraining]

I agree Auto Technicians are some of the most grossly unpaid people in the workforce. ~Ryan

[@yloow2]

This guy makes it enjoyable.

[@GoTechTraining]

Thanks for watching! ~Ryan

[@Bobbygale121]

Learned a whole lot, You are worth your weight in Gold my friend. Looking forward to the rest of the series.

[@GoTechTraining]

Hey Robert, Thank you for the kind words ! Part two is coming soon! ~Ryan

[@Mr18Chapin]

This is Gold man. Very informative & great way of explaining everything.

[@GoTechTraining]

Thanks for the kind words! It means a lot you enjoyed the video! ~Ryan

[@irishbob6771]

thanks so much for all the work you put into this. very practical and easy to understand video. much appreciated

[@GoTechTraining]

Thank you the comment! That’s exactly what I was trying to do!

[@emmanuelrobert1216]

You are a good teacher...Well done Ryan👍

[@nourfaheem3688]

Wonderful, organized and very helpful explanation. Thank you very much for you sincere efforts

[@Ricky-kp5ys]

Very good video the teaching was really interesting and easy to learn from,thank you for sharing your knowledge and experience I’m really looking forward to seeing more can’t wait 👍

[@GoTechTraining]

Hey Ricky, Thanks for watching! I really wanted to show how uncomplicated this can be with the right approach. Working on Part 2 now, should be out soon! ~Ryan

[@bnewton239]

i am glad you are doing this training for us. part 1 was great.

[@GoTechTraining]

Thank you, I’m happy you liked the video ! Working on part 2 now, should be out soon ! ~Ryan

[@arthurfricchione8119]

New subscriber who is trying to learn CAN SYSTEMS. FIRST excellent presentation. I have listened to it being explained to me before but this explanation is a terrific place to start and you explained it very well. It is so easy to become overwhelmed. I’m sure l’ll watch it over quite a few times I know I’m sure I missed a lot but it’s nice to know how everything is laid out before troubleshooting. Thanks for sharing. Artie 👍

[@GoTechTraining]

Welcome aboard! Artie! Thanks for checking out the video! I hope you enjoy the rest of the CAN Bus series! ~Ryan

[@sparknut5338]

Great logical analytical approach and explanation. Thank you for making these videos!

[@GoTechTraining]

You're welcome! Thanks for watching! ~Ryan

[@pakinayapantecatl9473]

I have seen other bus network videos but this one is the best one ...very well explain and learned a lot from your video...thank you and Godbless you ..👍👍👍🙏

[@A_plus_Auto]

Thank you ! your information helped me in understanding how everything works

[@FORDTECH313]

I have delt with communication problems many times not once have I used a lab scope thank God

[@GoTechTraining]

Hey Fordtech313, My scope is definitely not my first step in comm issues ! Thanks for watching ! ~Ryan

[@hometownautorepair3121]

Thank you for making this series, very helpful 👍🏻

[@wbrowning52ify]

Whether you are working on turn of the century or newer vehicles, this trilogy of videos will help you learn the steps to diagnose and repair the electronic systems with reasonable confidence.

[@gaberubio4733]

Thank you for breaking this down!

[@EastsideGhost]

VERY HELPFUL Information.. Cant wait for the other parts.. Youre the man RYAN..

[@GoTechTraining]

Glad you enjoyed it ! Thanks for watching and reaching out ! ~Ryan

[@-Primer-]

Well this explains the lack of "Accessory" wires in the multiple interior fuse boxes in my 2024 Sierra Pro. Plenty of constant power wires, but no "key on" wires to tap off of.

[@terrellscaife2411]

That’s really incredible. My weakness is understanding diagrams. I know that would help me out a lot on electrical stuff on the vehicle so I’m going to be watching your videos more often to up my game thank you

[@OshionamehJ]

I can help you start understanding wiring diagram.

[@terrellscaife2411]

Yeah, that sounds cool

[@JohnDoe-wv5hv]

Excellent education! Thank you much!

[@joemikos900]

Very compelling, great format. Always appreciated guys

[@GoTechTraining]

Hey Joe, Thanks for tuning in and showing your support! It gives us the motivation to keep making videos! ~Ryan

[@salvadorgutierrezr5914]

Thank you for teaching us Ryan 🙏

[@GoTechTraining]

Hey Salvador, Thank you for watching! ~Ryan

[@madmike214]

Outstanding I really struggle with communication diagnosed this will be an awesome series

[@GoTechTraining]

Hey Michael, Thanks for checking out the video! I'm glad you liked it! Part two is coming soon! ~Ryan

[@jrguzman1320]

Broooo!!! Your the man! Mothafuquen jedi! This video gave me hope! I am now confident and motivated! Keep making videos dawg! We need you!

[@troysmith9453]

Ryan thanks man just finished part 3 and I tell that 120 resistor 😊 I need to watch it again thanks alot homie we family now.

[@Jam-kq6hw]

Thanks you did a great job of braking it down made me want to learn more of this subject

[@alrifainidal]

thanks so much for all the work you put into this.

[@GoTechTraining]

Of course! Thanks for reaching out ! Glad you enjoyed the video ! ~Ryan

[@montanaautoworks]

This video is brilliant.You're a great communicator sir! Subscribed.

[@Gfitaliacorse]

Very nice explanation, professional, and to the point

[@ClintonSnow]

Excellent video, it's very well explained showing the graphic view for all the wiring diagram. Please do more video like this one.

[@stationaryenginesworldwide]

Great information. Looking forward to the next one part two!

[@GoTechTraining]

Thanks for watching ! Glad you enjoyed it, part 2 coming soon ! ~Ryan

[@on-site4094]

It started with emissions & keeps improving today it’s a a full fledged computer with a module to control each sector

[@superk4562]

Great stuff! Now we know why we have continuation training; there's always something new to learn.

[@ThunderbirdRocket]

You hit it outta the park ! Thanks mate !

[@GoTechTraining]

Thank You! Stay tuned for part 2!

[@timothyhowell3419]

outstanding presentation of a difficult topic for many of us. Thanks'

[@wentzelnel7723]

Brilliant lesson mate. Thank you

[@GoTechTraining]

My pleasure! ~Ryan

[@Sebastianx115]

Best explanation of can bus I’ve seen online

[@GoTechTraining]

Thanks for watching! Glad you enjoyed it

[@treyinok]

Looking forward to the next parts. Great work!

[@GoTechTraining]

Hey TreyInOK, Next part is in the works and coming out soon! Thanks for watching! ~Ryan

[@shamessun]

Thank you man …. your way and explanation is just so good

[@GoTechTraining]

You're welcome! Glad you enjoyed the video! Thanks for the support and reaching out! ~Ryan

[@TyFknGuy]

Great video! Was communicated well, very informative!

[@petehalasz7547]

Great video and narrator.. i teach for a corporation, and what's even worse is that 3 manufactures.. They have now stuck their parts in the same car and of don't get along. What's worse is information,, so like you,, I teach my techs to always,, always bring out the canbus schematics,, and split everyone up.. I have several vehicles which are completely gutted out, and we diag each group or groups... It becomes very clear and simpler.. Keep up the great work..

[@chrispeterson8402]

Awesome start!

[@GoTechTraining]

Hey Chris, Thanks for watching! ~Ryan

[@roderickzappareynolds2316]

Fantastic video Ryan! Thank you!

[@GoTechTraining]

Glad you liked it! Thanks for reaching out! ~Ryan

[@nimairikowa5650]

Thank you! can't wait for part 2

[@GoTechTraining]

Hello Nimairi, Working on it as we speak! Thanks for watching! See you for part 2! ~Ryan

[@ifell3]

After watching this I feel like a rich man driving my xp90 ^^ Fantastic video with practical targeting of symptoms.

[@GoTechTraining]

That XP90 will go forever!! Thanks for watching and reaching out!!! ~Ryan

[@ifell3]

@@GoTechTraining yes, since replacing the stretched timing chain as previous owner skimping on oil changes and a known TSB 😅

[@GoTechTraining]

Keep it going !!!!

[@Ianf1x]

To really help it would be nice if all manufacturers had the same can or lin etc colours. Yes there will be at least 10 different pairs and when looking at the module / node's it would be easy to see 2/3 network's on same module. Fantastic start. Been doing car electrics 30 years and I have learned a lot today.

[@GoTechTraining]

Hey Ian, Thanks for reaching out! I agree with having a little more standardization in wiring. Glad you like enjoyed the video! ~Ryan

[@AndrewLoo-dp9tw]

hey nice video. one of the best i've seen. Thanks. Im working on a same problem but I'm getting close to 10 volts on Hi and Lo line. still trying to figure it out. thanks for the video

[@nelsonmojica2000]

Thank you so much Ryan fantastic video!

[@GoTechTraining]

Glad you enjoyed it! Thanks for watching! ~Ryan

[@hernantoledo4418]

Thank you for the teaching us.

[@TurkVladimir]

Thanks Great Presentation

[@DavidFKturbo]

This was very well put together, Thanks a lot!

[@GoTechTraining]

You're welcome! Thanks for watching! ~Ryan

[@judodavid1]

Thank you for the knowledge

[@GoTechTraining]

Thanks for watching! Part 2 coming soon!

[@gatorgotme]

Fantastic instruction!

[@GoTechTraining]

Thanks for watching!!! ~Ryan

[@JuanMarcosONE]

Thank you so much for the information

[@najihusseini6679]

Very informative , thank you.

[@GoTechTraining]

You’re welcome! Thanks for watching! ~Ryan

[@westhomp1721]

Awesome video!!

[@TheMizarc1]

Awesome video

[@alexrojas2121]

Thanks for creating this. So helpful

[@GoTechTraining]

Hey Alex, Thanks for reaching out ! Glad you enjoyed it! ~Ryan

[@bartowl]

this is awesome material. Thank you very much!

[@GoTechTraining]

Glad you liked it! Thanks for reaching out! ~Ryan

[@user-mq1gu9pq1p]

Amazing video

[@djosbun]

Superb video, Ryan!

[@GoTechTraining]

Thanks for all the support Dave! Glad you liked it! ~Ryan

[@farmanyusif3558]

Well done thank you for informations that share with us....

[@GoTechTraining]

Hey Farman, You’re welcome! Glad you enjoyed it! Thanks for reaching out! ~Ryan

[@neilmcrobbie7010]

thanks for the info Ryan!

[@GoTechTraining]

Thanks Neil! You use your terminal test lead set yet ! ~Ryan

[@neilmcrobbie7010]

@@GoTechTraining not yet.....soon

[@balbie29]

Very interesting and I learnt a lot. Thank you

[@GoTechTraining]

Hey Balbie29, Thanks for reaching out and watching the video! Stay tuned for part 2! ~Ryan

[@vernaltheuberdriver.3491]

Love this lesson. It’s a lot of have issues with this.

[@GoTechTraining]

Glad you enjoyed it! Thanks for watching! ~Ryan

[@FORDTECH313]

But I have learned alot from your channel and I am thankful I have been on my own now for 4 years these cars are getting more difficult to work on but not only that lots of customers are getting more short tempered patients is a thing of the past as techs we don't just look at one or two cars a day some easy and some very difficult sometimes we can look at one to nine cars in one day I love working on cars I enjoy seeing customers faces when there car is fixed they get so happy but everything is changing the world is changing

[@GoTechTraining]

I agree! Some days are good, somedays they get the best of you. As long as Techs likes you still find the pride in their work and stay positive through out the change. They will be successful and come out on top of the “automotive revolution” as I like to call it. Keep wrenching and feel free to reach out if you need a second opinion. Every time I feel i finally caught up, some car comes and kicks my butt. Thanks again for reaching out ! ~Ryan

[@FORDTECH313]

Thank you I sure will I appreciate it

[@johncasady7552]

Loved the video and how you break things down. I will definitely be watching the rest of your videos. Curious on what subscriptions you use for wiring diagrams. --- I answered my own question by reading the comments 😂

[@mokhtarmpower8421]

Thank u really great explication

[@steelcitycaprice.899]

Great post 👍🏽🏁🏁🏁

[@hhn2002]

This is so good👍

[@saibabupodala6297]

Very good information thank you

[@GoTechTraining]

You’re welcome!

[@tomhague1162]

Very well done. Now I can have a far more intelligent conversation with my mechanic. We can now talk the same language.

[@dailylifequotesforsuccess]

i really appreciate for the content!

[@BeccaLovesGleee]

Hey Ryan ,very well explained 👏

[@GoTechTraining]

Hey BeccaLovesGleee, Thanks for watching! Glad you enjoyed it! ~Ryan