Elite diagnostic skills, keep up the good work! Had a tow in one time too, at the DLC CAN +/ CAN - showed 2.5V/2.5V when testing with a multimeter. TR was 120 Ohm indicating an open somewhere on the BUS. Car was in front end accident - went to the main harness running across the front of vehicle going into the PCM. Scope PCM CAN +/ CAN -, both were spiking to 12V. Further basic short testing found the CAN + wire was rubbing against a pinched 12V wire in the harness!
Hey I love your videos, can you please clarify the open circuit on the picoscope and what it looks like? I was kind of confused at the last part. I love your videos and explanations thank you
@@simmsimmerson6039 Ah ok, it’s hard to explain via a comment. Because of the terminating resistors, CAN high and low are essentially connected. When we add an open circuit, only one of the wires is communicating, this has an effect on the open circuit wire because they are ‘connected’. If you search on Google You can find a diagram of how the transceiver is connected inside the module, and how the voltages are created. It might help make more sense. If you see my other video checking Low speed CAN, this doesn’t happen because high and low aren’t connected by terminating resistors
I owned a Chevrolet Captiva 2.0L Diesel (2010) and lately the car faced with many technical issues. Thinkcar scanner had identified 7 issues with ECM, 2 issues with TCM and 3 issues with EBCM. ECM 1. P0700-00 TCM requested MIL illumination 2. P0571-71 Brake Switch Circuit 1 3. U0140-00,U0144-00,U0104,U0101-00, U0101-46 Lost communication with BCM/CIM/ CCM/TCM/TCM TCM 1. U0001 CAN Bus communication 2. U0401-00 Invalid data received from ECM/PCM EBCM 1. U2107-00, U2106-00 Lost communication with BCM/ TCM 2. C0561-71 System disabled Information Stored Invalid serial data received . I only owned a scanner and a multimeter. Can you guide me how to resolve the above issues. ? Thank You and best regards.
hello, i dont have scope handy at the moment but just noticed something on my car... i have some "no message" codes in pt-can.. the voltage on CAN-HIGH is below 2.5V and CAN low around 2v.... if i meassure with only 1 ecu connected to the network CAN-H sits at 2.7 and CAN-L sits at 1.7..if i introduce one more ecu to the network CAN-HI drops around 2.3v...any ideas? i removed on ecu from the network at a time but still no change...
Hmmm, not sure. If you are reading codes from that network then there must be communication. Would be best to see actual waveform. I played around with some resistance on CAN and it is surprisingly robust. I did a video somewhere. Remember, if you can read the codes from the module, the network is probably fine
@@MechanicMindset thanks for yoyr answer .is something strange...i start the car...an as soon as i start revibg it..i can see the transmissiin gear indicator disapear from the dash...and the reapear as if the dash would stop receiving messages from EGS...i will scope it tomorrow
Your videos are fantastic. I have learned so much from the videos and the courses I have taken from you. My 07 Ram 1500 truck has a can C issue. With the Pico 2204A connected to CAN C high and low at the OBD2 port, it shows shorted together at 2.5V. But, if I disconnect and reconnect the battery, the network shows normal until I turn on the ignition then it goes back to shorted. I haven't had a chance to do anymore testing, but my feeling is that it has something to do with the transmission module because that is the only module that does not communicate with my scan tool.
Hi, this is a high tech video for me, but I thought I'll pick your brain on something I am looking for regarding CAN bus. I have the Realdash android app and I am using it as a digital dashboard to display various parameters by connecting to the OBD2 port via a Bluetooth dongle. The app is not able to recognise when my car is in Reverse gear and therefore the gear display gauge is not showing 'R'. The app needs some sort of a signal from the vehicle to indicate reverse gear. I have a BMW 320d 2017 model. Is it possible for you to read your BMW vehicle CAN to dig out this information about the status of reverse gear so that I can configure it in Realdash? I don't know whether it's a PID number or something else. I am just trying my luck. Sorry if it's a silly question. Thanks!
Hi, sorry I’m not sure what will fix your issues. Although the reverse signal message will be sent on CAN as it has to go from transmission to FRM and IC for lights and cluster. I’m don’t know how you you’ll get your app to recognise this. I suppose it depends on what it’s capable of communicating with (ie some apps/dongles only pull OBD2 standard data)
Another great video. I love how you show the different fault can manifest themselves. Just curious, if, when troubleshooting, you remove a module that contains the 60 ohm's resistor, would you place an actual resistor to complete the circuit and see if the signal clears up? If the answer is yes, would a regular 1/4 watt, or 1/2 watt be sufficient? Keep up the good work.
Stephane Chabot Great question! I have not tried this. There are so many combinations of fault to be had in CAN bus and I plan to explore this more for you all. In theory, yes, if you put the resistor in the correct position in the circuit. Not sure on the power rating but CAN doesn’t really draw much (if any at all) current so should be fine. Think I might have a *120 ohm resistor so will give it a go. Thanks for watching, glad you’re enjoying the channel!
I got my first scope today, 6022BE. I'm trying to diagnose a TCM communication issue. The signals I get are both the same (one isn't inverted), basically CAN high seems to be the same as CAN low, like both signal are being pulled down instead of CAN high going up. And the signals seem to be more stuck together with a kind of a jump half way up. My initial thought was that CAN high and low were shorted together, but judging by this video this isn't the case. And I get a 60ohm reading on the line so it doesn't seem to be a a break or a short. Of course it could just be me screwing up something, I thought that maybe the Hantek software might have automatically inverted one of the signals. There is an "invert" tick-box on the software but it doesn't seem to do anything. I thought it would maybe invert the signal. The car runs fine, it's just that the TCM randomly has a few errors. I'll probably have a better idea once I get a bit more used to the software and see what a good signal looks like. But this video was really helpful. Thanks!
@@MechanicMindset Yea, the 6022 is great, but the software is a bit annoying at times! I was using the leads that came with the 6022 and I had them connected to back probes for the wires and crocodile clips to the battery negative. And I was back probing the CAN wires on the TCM connector. But then the next day I tested the signal on the multiplug and I got a perfect signal. So maybe I just screwed up something, or maybe it was a glitch in the program, or maybe the wiring at the TCM is messed up, but I don't think so because 99% of the data I get from it seems fine on the diagnostic tool. I did find that the signal was a bit cleaner once I removed connectors on the battery negative. My next plan is to test the signal at different connectors, pull some modules, and shake the harness about to see if the signal changes, but the trigger is a PITA on the Hantek software!
@@JoeBob79569 If you can read data from the module, CAN is OK 👌 There are some other software available for the 6022be, HScope if you have an Android device. And another called open Hantek or something. Not tried them though 👍
@@MechanicMindset Thanks. Yea, I finally got Open Hantek running earlier, I had to install some framework files from Microsoft to get it running (visual C++ I think), probably because of the way it was compiled for GitHub. Haven't tested it out yet though. I couldn't get Hscope working I think you might have to buy a licence, but might give it a shot at some stage. It'd be great to have the Pico software for the Hantek scopes!
@@MechanicMindset So, I'm sending the Hantek back to Amazon and I've got a Picoscope 2204A on order instead. The Hantek software is far too primitive, it's like they just don't care, about it, at all. Pico seem to be a lot more professional, and there's probably a lot more support on forums, and the like, since so many people use Pico. And also, automotive!
Can i just ask the question. When you connected the leads to the can high and low you also fitted a earth lead. Where did the earth lead connect from when the other end was clipped to the car earth point. Great video and easy to understand and gave me lots of confidence to attempt these types of faults in future.
The Retired Mechanic, do you mean the end that connects to the scope? It is similar to an old TV areal connection. The inner pin is the red lead and the outer part connects to the black lead; these leads are actually made of coaxial cable. Look up BNC connector, that’s what this scope uses. Happy the video helps!
Good question, if it’s a broken wire, you can see it on the waveform. If it’s an open circuit in the module, we’d have to confirm the wire integrity with continuity 👍
Pretty much any windows laptop will do it. There are so many out there it’s hard to decide. Personally I like Dell products. Also have a couple of older thinkpad laptops that work well. Of course you can get toughbooks which are good for the workshop
Hello, I am trying to learn automotive electrical diagnosis. At about 6 minutes you mention shorting shorting to ground and shorting to positive. That's for where you are connecting the measuring device? So you would have the measuring device between CAN low and positive power on the car, ie red cable? I don't understand that part, don't you risk damaging the circuits if you connect back to positive?
Hi - wonder if you could offer an insight into a curious wave reading I am getting with ignition off.....2007 Disco 3, ignition on CANBUS looks good, with ignition off it doesn't flatline like my BMW does - it acts like Low is shorted to ground.... vid here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-jkmKnNxJ_qk.html - is this correct?
thanks for video i am confuse now because in your other video you proved that high speed CAN BUS are robust and they work fine even if they are shorted .but now you contradicted that
ali batebi Hi, in this video I am demonstrating ‘dead short circuits’, for which CAN bus has no robustness for. In the other video I am showing that if there was a high resistance short circuit (like water corrosion) CAN bus has some defence, but you will remember that at some point it could no longer function. Sorry for the confusion, I will try to explain better next time! 👍
I have a fault with a mercedes E Class 2016 in the CAN I lines from the ECM N3/10 I have 5v on the can high and 0v on the can low with ignition on. I'm not sure what the problem is. I had an open circuit in the can high and repaired that and this is now what I have. Please help.
You get slightly better specs for sample rate, but the resolution is the same. I think the 2204A is fine for starting. If you want to spend a bit more money get the 2405A 4 channel version. Otherwise, get the 2204A, and if you like it, start saving for the 4425 👍
After seeing several videos of people using the pico 2000 series in the automotive industry I got very curious (since I can't afford the 4425 series). So I went and bought the 2206B 4 channel and yesterday I had the opportunity to use it with my ODBII breakout trying to see CAN low & high (i did that on 2 E46 BMWs) and I got the same results, not square signal, one edge was rounded. There was a curve line from 2.5v all the way to 3.5v and same the low CAN, from 2.5 to 1.5. Any thoughts on why I'm getting that rounded edge? Do I have the wrong settings (A & B +/-5v, time 20 to 50 us). Thank you in advance and keep up the good work you do with your videos helping everyone. Love your videos.
Jorge Andrade Congratulations on your purchase, powerful little tool! Hmm, can you see a whole data package on the screen; start to finish? (Does it look like mine). Just wondering if E46 CAN speed is slower, try increasing your time a bit. 👍
@@MechanicMindset Thanks for getting back to me, I believe I save the file and tomorrow once I get to wk I'm going to view it again and somehow send it to you. I think the data package is there, it's just with a rounded leading edge. The edge going back to 2.5v is a straight line on both high & low. I will get back to you, thanks again for taking the time.
Thank you for your video. I thought there was a PT-CAN issue because I have 2 EKP modules that won't respond but if it's supposed to run at full speed as a failsafe that means it's a power/ground issue, right?
i was trying to do this through the OBD on my E90, but i was seeing nothing on all lines, do you know if there is some detection the car does or something before it enables that port?
Sorry, deleted my reply, thought you watched a different video. My mistake So I think the reason you can’t do this via OBD on an E90 is that the OBD on these later vehicles doesn’t have all the CAN networks in that connector. We have something called D-CAN (diagnostic) that goes to the gateway module; the gateway has all the CAN networks connected to it. I would have thought you would get something though. I would have to check
@@MechanicMindset great thanks for the tip, i'll look into that, i recall seeing something about d can but just assumed it had the reular can lines anyway
So in theory I could get a waveform generator connect it to the wire or wires(my lancer uses 2 wires on certain components) generate that waveform and if there is a communication error then this would make the two components communicate or believe they are communicating enough to see if the component is to blame or it's a communication error?
Hi, I haven’t seen any waveform generators that transmit on CAN like that. The best way to check if there is communication, is the scan tool. If you can read the codes, it talks. This video might help with diagnostics ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-k8bJegVxo_c.html
I've got a very unique problem with an N51 328i X. I'd like to talk to you about it. Seems like I'm chasing a ghost. Maybe we can both learn something by talking about it.
@@MechanicMindset It’s based around mixture control and misfires but I’ve already swapped everything anew. New purge valve, MAF, Bosch coils, NGK sparks, pre cat 02 sensors, manifold seals, throttle body seal, oil filler cap, secondary air hose. I’ve cleaned the fuel rail and since it’s an N51, I highly doubt the injectors have gone bad. At this point I’m suspecting it’s an electrical issue.
@@MendyHazan Ok, have you been able to confirm what the mixture is actually doing (via 4gas or O2 readings). Any fault codes? I have seen Super Mario Diagnostics channel do some walnut blasting on intake for running problems
@@MechanicMindset I’ve checked the needles when I replaced the manifold gaskets. Clean as water. I get codes for mixture bank one and two and misfire for 1 2 5 and 6
@@MechanicMindset Nothing in particular. I ask because I have the same scoop and anything using this scoop will be appreciated. As this is my first scoop and I love it. I'm not very good but I am learning. Thank you again for the hard work you are doing. keep safe and all the best.
@@MechanicMindset I'm desperately in need of help, I got multiple K-CAN line faults and possibly it's wire shorts somewhere and I don't know how to fix it, I was thinking if these is an experienced guy like you here in London
Khaldoon Atiyah Hey, Sorry Im midlands based. I don’t know anyone down that way. I do have a video on KCAN that might help. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ncQfdhzUFCk.html
@@MechanicMindset thanks mate for the response, may I have your contact details, you may send them if you are okay to khazay@hotmail.com, may have to discuss few things over the phone that might help me to pin point the defect, I'm aware that I should be charged for your service. Thanks for the support though
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