Anyone hear of schools/schooling/literature for those of us that will self teach as to how the systems function work and progression of actions internally? All too many manufacturers are going this route including motorbikes, autos, HE that knowledge of this electrical wizardry is almost essential now. Have been discussing this with others where a few are getting SOME instruction from OEM sources but still not much as to level of prowess as to actual form and funtion.
CAN is almost obsolete. Nowadays its backbone 1 & 2. Network speed fast enough to run the government efficiently. In the early networks J1587/1939 everything communicated on a single network of 2 twisted pairs. There was the slow link and the redundant fast link. Then they introduced CAN which stood for controller area network. Only functioning electronic devices could communicate on this network. Diagnostic tools are not allowed on this network. The communication takes place with low voltage signals of dots n dashes. CAN low is typically less than 2v and high is usually around 2.5-3v. The dots n dashes are more like dwell time of on and off. This takes place incredibly fast. You can see it with an oscilloscope but we can't read it, it's like trying to take a sip from a fire hose on a pumper. The first bit of the "package" identifies the MID or module identifier. The second set calls out the SID or PSID which is system identifier then comes the FMI or fault mode identifier. So you would get , for example, 128, 96, 6 that would translate to engine, fuel, data valid but below desired. . We can go deeper than this, there's a lot. I'll see if I can find some good info to share in my home laptop.
This is pretty involved, maybe a better description than I gave. https://www.kvaser.com/developer-blog/an-introduction-j1939-and-dbc-files/
Saw that one FWF, was thinking may be better as to instructional courses to explain the algorithms and data transfer slot ID establishment. Something better than it functions or doesn't. Harleys after mine began CAN-BUS use, lighting ignition etc. where splicing harness became an all NEW Art form. Have noted it in the 2017 Ford we own as well. OBD seems OK but is hard to switch into. Just trying to stay in the game enough to work my own crap!!!
Oh, in that case it works like a 727 mopar trans. Black magic and voo-doo
Already had dealings with Magic Electrical Smoke, is really tough packing that stuff back in once released.
"CAN is almost obsolete" that's pretty common for me. About the time i need to start learning it, it's already obsolete.
There's current production and NOS it depends on the supplier. Its supposed to be like vatozone antifreeze. Cross compatible with all coolant regardless of Mfr claims.
I've been working on a Deere 310SJ TC backhoe that is totally over engineered. The pilot controls system is completely fly by wire, it has somewhere around 10 computers on it along with multiple sensors all communicating via CAN BUS. It was loaned out and the people using it hit an underground power wire. Of all the backhoes to hit an underground wire, this was not the one to do it with. The pilot system is completely dead and part of my diagnostics obviously is the CAN system so I am also looking for any kind of info.
That really sucks, most likely surged every ECM, would suspect every sensor as well, same as throwing a arc weld on a machine without disconnecting batteries.
It’s funny, I was always taught to unhook the batteries before welding on any machine but I’ve seen guys that actually weld for a living and people that don’t know anything about it just strike an arc and go to work and they never have any problems. If I forgot you can bet the farm that I’d fry every electronic device on the machine.
On the Volvos, we would unhook every ECU. There could be as many as 7 or 8. Always ground as close to the work as possible. Personally, never had an issue. Fixed a few with lightning strikes, poor welding practices and unregulated jump starts. Good times , expensive mistakes.
When I worked for Volvo we just unhooked the batteries. Ponsse on the other hand had a procedure that had to be followed step by step before welding and reversed when hooking everything back up.
There is a neat tool that you can plug into the system and it will identify every sensor and device that talks through the can-bus. I just learned about it and I am still doing research on how I can make use of this for troubleshooting and bypassing. It is called a can sniffer. So far my research has only brought up automotive applications. When it comes to equipment it's the wild west and everyone does things a little differently.
Oh, I like that. Let us know if you find anything, meanwhile, I'll be googling tonight.
I have a customer who bought a used Deere 200lc awhile back, it sat for about a month with no problems. Started right up after sitting, had a local weld shop come out and install a thumb, they were there 3 different times and I was there fixing electrical problems each time after they left.
More than 10 computers on those puppies. Now you know why Deere stopped making them.
CAN is fun. Floating network, 60ohm (ideal) +/- a few ohm resistance, twisted pair wires, two 120 ohm terminating resisters (sometimes one resistor will be In an ECM itself). My OEM is phasing in Ethernet, as CAN is too slow for the big data now but still tons of CAN in current and recent machines.
Ethernet over what kind of wire? Interesting. So far all I have seen, worked with, or been aware of has been CAN or similar.
CAT training video for CAN diagnostics. Basic but very informative. https://channel1.mediaspace.kaltura...leshooting+(ElectroNicks)/1_lbevo0xd/96189352
Thanks MG Thats good shirt
Look up ScannerDanner on YouTube he has lots of good info from the aumotive side.
They have lots of videos but some of them it will not let me see. I guess they are dealer only.
Most or 95% of of problems I deal with in the shop is located in connections and the wire it's self. And some of the trouble shooting is easy like harness to DPF is MELTED. As far as anything related to the computers or sensors - those folks can have it at the dealer. I'm not a TV, Appliance repair turd. You can't do it all folks sometimes you have to blow the dust and cobwebs off your wallet and keep the young fellers at the dealer employed . Or go back to basics and use a rock and a rock to tenderize your chuck steak. And when I get to a point in life I will throw the keys away and take the bus.
Mike, does your boss have enough clout at the dealer to get the bill reduced when it turns out the young feller was just wasting time with the computer because he did not know what he was doing or was not properly trained? We go to great lengths to keep the electronic stuff in house for fear that the dealer will just screw it up worse. Our problem is the manufacturers are so secretive, they won't tell you how it is supposed to work (or don't even know) but they don't really know how to work on it efficiently either.
Dealer covers it, And I know what your talking about when it comes to a dealer working on it. We have a select few to send them to. But I'm not playing privet eye on electronic crap either. Most of the electronic/computer wear in trucks/or anything really is all about marketing and they don't want you tampering with it. I started working on computers on electronic fuel injection back in the 70's-----Anyone ever hear of D-Jetronic? I'm hoping for the day it's all robotic, robots design it, build it and repair it - and man can set and do nothing and whine about what he created-and no one works.
I am with ts on this Started working with mechanical diesel points carbs lp conversions on gas Saw the onslaught of varied electronic ignitions fuel induction systems proprietary bs you could not get info on as the first Caddy electronics that were the predecessor to CAN systems. Detroit dropped the first DDEC systems on us we could not do much with where they would not warranty much. Then everything went proprietary in nearly every industry the Fed stepped in to drive common technical diagnosis on cars that did not last long where here again all has become proprietary a PITA and increasingly troublesome to diagnose. Needs of special tooling computer programs and equipment that obsolesces faster than the systems designed for. I take much to dealers as no longer have the money to throw to this stuff or the time to learn it as it seems without expending a lot of money so may be already getting on that bus. My Harley is two years before CANBUS My pickup antique my old tractors nut and bolt simple but are all getting to the lack of hardware stages as the manufacturers obsolesce repair parts. Can still make some but not all of the needs.
One big problem especially with Daimler, Detroit, Freightliner the only way you can keep your warranty intact is repairs have to be documented by Detroit. If not they can and will step out from under. Plus you can't keep equipment past warranty.
A bit off topic, computer wise, but this reminded me of back in around 1970 I owned a 1966 Corvair that the four speed transmission went out in. I had no place to work on it so took it to a Chevy dealer. After a couple days check with dealer and got the story that nothing had been done to it because the mechanic assigned the project threw a fit and said he told them he wasn't going to work on those things and took his tools and left! Hate to think what that guy would think of cars these days if that Corvair freaked him out! We actually moved it to another dealer next town over and a few days latter had it back with a good used transaxle. Jump ahead a few years I had another Corvair, yea I was sort of addicted to them at that time, it had this noise in the clutch area. I had an old cow barn to work on at that time so dropped the drive train and replaced the clutch thinking it was weak damper springs. Some-of-a-bitch! still had the noise. Stopped by the dealer, as I was told they liked Corvairs, near me, a small maybe three stall repair shop and display floor that was lucky to hold two cars, at that time. Service manager came out and listened to it idle and said "Bad flywheel" they have a flex-plate riveted to the flywheel, rivets get loose. Parts department actually had one on the shelf. Drove home and had it in and car back on the road early next day! Nice thing about doing the same job two times in a row nothing is rusted up and you know where every bolt is!
Makes me feel even better fixing the old truck !
Case in point--A little over a year ago one of our Freightliner Cascadias had a major issue with the DT12 transmission. It refused to talk to engine controls, it was at a dealer for six weeks while they tried everything which has to be run through Detroit Transmission before any repairs are made. Detroit tells them what to do. Finally Detroit authorized replacing the transmission. A DT12 costs $18,500. I can't touch one of those in the shop, I repaired/rebuilt Eaton 13's, 10's, 18's for years but the autos have put me out of work in that area. Now for you automatic lovers just go out and buy a dump truck with a DT12 and about 400,000 miles on it. You will be crying all the way to the bank, If you can't drive a stick then you shouldn't have a CDL. But the industry has made us lazy as hell.
We were doing a tandem lift on an engine module up in the Yukon a few years back ,we had the old P&H 125 ton set up on one end and the 90 ton Link Belt on the other. Go to lift and the Link Belt craps out ,no one around to figure it out until a guy from the local Cat dealer rescues us. Something to do with its cleanout burn. After that id bug the guys ,the old triple nickel Cummins in the P&H chugging away blue smoke coming out the twin stacks. Its just doing its cleanout burn id tell them. Another old machine always ready and reliable.
I know they are probably not the best transmissions ever built but have to believe if you totaled the price of the parts I put into Mack Quadraplex transmissions over 30 years working on them I would probably not have much more total in to all them!
I would average about $1,800 in parts on a Eaton 13spd. Freightliner---when everything goes dead in the cab-nothing works-dome lights, AC what ever you don't need anything but a multi meter to check the alternator out put. If alternator only slightly over charges the system will lock out to stop the surge. Sam