CAN Bus Communication Explained (Part 1) 

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.

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.

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!

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

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

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

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 👍

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

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

This is the greatest lesson I have ever seen.

Very good explanation of the CAN bus system. Your video gives me a three dimensional way of thinking for troubleshooting a system. Keep them coming.

I have to say i have watched several videos on can network and the way you went through it was absolutely the best look forward for the rest

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

You hit it outta the park ! Thanks mate !

Thank you for teaching us Ryan 🙏

Thank you! can't wait for part 2

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

Excellent video, Very helpfull, thank you very much.

Thanks for taking us on-board guy's👍 Stay Safe👍

Very compelling, great format. Always appreciated guys

Very informative video but the catch a lot of time is access to the drawings that show the buss arrangements and hookups.

Now that was some good stuff!!! Thanks a bunch Ryan. Ill be keeping your remark on how this is all just "glorified map reading" in mind. I also agree that it is beneficial for us that all the different modules are linked in different groups allowing for us to just observe patterns and figure out the common factor if presented with a list of trouble codes. Now what would one do with out a "CAN MAP?" Not sure if any one has ever told you and Im certainly no expert but it seems to me that you're a natural teacher.

Very interesting and I learnt a lot. Thank you

Hey Ryan ,very well explained 👏

Very good information thank you

Love that term "glorified map reading". As a big map buff I know that having free access to decent maps like Google Maps was a crazy good breakthrough. I like how you have built some good simple flowcharts for this, but it might be good to call out what reference diagrams you are looking on screen. Folks in the industry might recognize the screens but folks who tinker with cars as a hobby might find the cost of entry to this stuff is prohibitive.

Thank u really great explication

Bro your stuff is better than getting a master degree at Harvard

great effort , thanks ❤

Sounds like how wiring is simplified, with the added benefit (for the manufacturers) to control what you do with your own car. Which to me sounds like you do not truly own your car anymore, or metaphorically like riding a horse that doesn't listen or obey you. Only 23 but I'll drive pre-90's GM's the rest of my life! (Edit: Still great info to have! I'm the only car guy in the whole friend group, and I always help everybody out.)

These modules are car specific, right? I mean is there actual hard coded software in each module?

Great 🙏

Where do you get these network wiring diagrams from?

Thank u so much!

Hello, I have Volvo I shift, with fault : mid 130 psid 232 fmi 9 Customer brought another trans, I checked on bench and still the 2nd transmission shows same fault, but the way I checked all yellow and green lines all over and ohms were around 60 ohms

WHAT ABOUT WHEN THE FAULT DOES NOT STAY ACTIVE COMES AND GOES (INTERMITTENT) ANY IDEAS

21:13 you say that, but a BMW with keyless entry won’t start if the sensor in the passenger handle shorts out, you can’t even release the electronic hand break. That’s still single point of failure in a design that has 50 networks, in a sub system that has nothing to do with running the engine . Clever? Certainly. Smart , debatable.

👏

I have a Yaw sensor (ground, can-H, can-L, ignition). I have provided ground and power, should I get Can bus signals from the sensor itself once I start moving the Yaw sensor?

I have a problem with a Porsche Cayenne of 2013. The Gateway stays On all time ,even if the car is locked

please sir where do you get the schematics from

The clouds have split up and I see the light.

At this point can we just call it a “Can’t Bus”? I have 3 carbureted cars from the 70s and one from the 80s in my yard and I am seriously thinking of giving up on the present. It doesn’t matter if computers make things more efficient if the engineering doesn’t hold up and stay working… I drive faster and cheaper with a carburetor than walk. FYI I was a computer programmer and hacker in the 80s and I know how they work I’m just tired of needing a way too expensive tool to fix things that are made to break

Need to input tools parts numbers

My problem starts when obtaining any schematic information from the manufacturer, (BMW), is impossible and access to the most basic information has been monetized and you’re required to pay through the nose for it. Nowadays doing it yourself is impossible because the information is restricted purposely. Obtaining wiring schematics for my 2000 BMW M5 is a nightmare.

So in a Zombie crisis don't use modern cars... Got it!

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

Rather than multiple networks, I think the solution to not shutting my engine down when I spill a drink on my window switch is for engineers to realize that my ECM doesn't need to know the position of my window.

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

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 ! 😃

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.

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 👍

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...

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!😅😅

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.

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

Thank you so much for posting this awesome video, Ryan 🙂it was the best explanation on the entire Ytube, really made sense, looking forward to viewing the other material that you have so kindly posted, keep up the great work. i have a Mercedes W205 here in the Shop with innumerable problems, and i hope to get to grips with it, certainly i feel confident now after watching this video, Bless 😇

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

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.

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

Nothing less than fantastic classroom teaching in relatable language. God bless you for doing this for all us tech that are in the game from years ago as you e given us a training course that was just not available unless we were in main dealers. I'm getting back into the trade after a decade away and hearing that it's impossible to get a good tech these days. So thank you so much for paying it forward. Your a great teacher and top tech.

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.

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

Ya'll vehicle technicians need to study Cisco Networking or Comp TIA Networking.

what are you talking about, why are you arguing with the 3rd person, your really arguing with how you ere thinking about it in the past yourself. go speak to a professional, and say "why do i argue withmyself, and then prove myself wrong, and feel like I won"

Yes, it can!

Hy Ryan please help me with wiring diagram software what wiring diagram software you using and which one you recommend me to buy

LEARNED NOTHING I´M AFRAID; STILL THINKING OF A SCHOOL BUS SHAPED LIKE A CAN; BEFORE DIVING IN, I NEED TO KNOW WHAT IT IS.... »»»»»» SO WHAT IS CAN BUS? IS IT WIRES?? THE OLD SCHEMATICS OR WIRING DIAGRAMS? IS IT ICs, CHIPS? IS IT THE SOFTWARE INSIDE CHIPS? ETC *WHAT IS* CAN BUS

Glorified Map reading- great stuff- Big Thank You!

Great video! Only thing was u sucking in ur nose hairs , can’t listen to this when u do this

Encapsulation, like tcp/ip!?!?

Typical another how a can bus system works just basic info one of the thousands out there. When are theses guys going to explore the can messages and sending commands to modules using UDS protocols no stuffing around with live data. Sending write data by identifier commands, security access$27 requests, enable programming mode, hv wake up 0x100

Bravo.......u show canbus .......but no resistors on each end 150 ohm .......hmmmmmm..........cheers

My ECU blew 2 times and I had to print out the ECU/CAN lines and Crayola them for the dealership at the time to have them actually fix the problem for the third ECU... you just validated the entire video with that one line IMO.

This guy makes it enjoyable.

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

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!

Uhh,this car hobby is turning into something very serious for me.

Ok,what's the name of the Scanner that has Topography?

Do you have a way (or can you build something) for the Holley Dominator to work with the OE CAN system from the IRS from a 2018 Camaro ZL1 (graphed into a high-end C-10 build) We've used the IRS's LSD with a crude control system (switches and a rheostat) for track use, but need a system for street/show vehicles to use this suspension/diff system. There are so many adavantages of GM's IRS, we think this integration to Holley's system would be game changing. Thanks!

Wow This channel is getting good 40000 hits 200 comments

Looking forward to the next parts. Great work!

I've watched to part3....If you wish to learn and understand well...please don't miss this series

Another case of "blame thy neighbor" My Silverado and my Jetta use this technology heavily, my F150 uses none of it - the Silverado will shortly be a scrap yard chunk because of this tech - it's worth less than the cost to repair it, the Jetta so far has behaved, but will follow the Silverado once it behaves the same, the F150 is 28yrs old and there isn't an issue that can't be diagnosed with simple tools and in short order. CAN tech was the only viable answer to the rolling, self driving, personal assistant, infotainment system, that the public is enamored with. Even with this major relief from 7 miles of wire per vehicle, the weight of cars just keeps climbing, and they keep getting more and more complicated - if there's resentment against this kind of tech (I do), it's that people lost sight of what transportation is.

Question: How is it that I have a F250 that has no communication DTC's, but has 120 ohms Across six and 14 on the DLC? The only problem the truck had was it needed a headlight programmed.

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

i see some of it but like many cars you cannot turn off unless you unplug the abs module// abs shouldn't have anything to do with switching off vehicle. you buy new vehicle someone steals radio might just total the car you cannot drive home there needs to be work arounds. you cannot even buy a new vehicle without a radio shouldn't be that way

Do you explain as well the 19--Gateway Data Bus Module where there is no communication ? This a puzzling issue i am having with my 07 Audi Q7 V6 3.6L FSI Quattro with premium package suv. I have access to the vehicles software. I have a No start ...

7:08 unfortunately automatic breaking systems don't necessarily always stop the car for you completely. I have experienced this a few times (without crashing) where the automatic breaking released at the last second and the driver has to stop the vehicle, I think this is for the manufacturer to avoid liability if there is a crash.

I have a older commercial truck that does not have a ECM. I’m looking to have the truck speedometer communicate with a logging device which is cam bus. Is there a way to have the truck tell the logging device it has started to move or dictate motion. Thanks in advance

Module rebuilding- With increasing shortages (ha) delays and back orders on failed modules, is rebuilding modules a feasible option to get people back on the road? The obvious answer is no: can’t guarantee results, incorrect rebuilding, etc. The not so inobvious answer might be: if the module is 6 months away, a commercial truck probably wouldn’t even hesitate. Maybe.

Esto es muy fácil para mi . De encontrar . Cómprate una Scanner. Autel ultra , Esta te ayudará a saber lo módulos que están muertos y los vivos. Otra cosa que puedes hacer es desconecta el ABS y fíjate si hay un cambio . Desconecta el tablero . . No seme hace difícil .

Question about a break out box. Do they work on a network with a gateway module? I have watched your videos and it seems to me they can only read between the DTC and the gateway.

Heavenly Job man. Can't thank you enough. Where can I download different network for different manufactures ???

God bless you for giving us this information...I'm at a lost now trying to find out why my fuel pump keeps dieing..have 12v at wire hardness 9.8 on ground. Don't know why..new relay..

I think I have one of those House Of card scenarios on a 2007 GMC Yukon XL. I took it to the dealer to have them diagnose it. They replace some parts and said they cannot figure it out so they told me to come pick up my car and it is been sitting for 2 years and still is not fixed. Every time you turn the key to start the car, it will fry the BCM. Thanks for the information. Hopefully this might help me diagnose it.

The definition of freedom is the ability to move how you want, when you want, and using any clean free energy source you want. It is a good practice to listen also. GoTech quote, "You'll go nuts trying to look at this all at once". Freedom is NEVER easily gained! As Paul Pantone once said, most inventors trying to obtain freedom through their inventions end up in the nut house!

HI SIR I OT2012 CHEVY 3500 U0101.& U00.73 NO TCM. I CHENGED TCM ECM NO LUCK GM TECH CAME NO LUCK PLS IVE SOME .SOME INFO

Would you happen to know if a CHARGER RT 07 has CAN BUS ? Thank you

Yep, way too much stuff you don't need :) Give me a simple in line 6 or small block with a standard trans floor mats wind up windows. :)