Forum Replies Created
-
Replies
-
When OBD-II came out and until very recently, there were five protocols that car manufactures used to communicate with a OBD-II scanner. They were Pulse Width Modulation (Ford), Variable Pulse Width (GM), ISO 9141-2 (Some Chrysler, European and Asian), KWP2000 (mostly Asian) and the CAN bus protocol. Basically they all had different communication networks, but they all had to meet the criteria of the OBD-II standards and have standardized diagnostic trouble codes. This is why when you look at a diagnostic link connector there is 16 pins in it. One pin is battery voltage, one pin is chassis ground, another pin is signal ground, but the rest of the pins are the + and – sides of all those protocols.
After 2008 (I think), all cars made for the U.S. market have to use the CAN bus protocol. This has a higher data rate and allows all of the various modules to communicate efficiently over fewer wires. It’s still technically OBD-II and will work with OBD-II diagnostic tools. When OBD-II came out it really didn’t standardize all the computer systems, it just included all the communications that the manufactures currently used. It also standardized all the trouble codes, so a misfire code in a GM would be the same code in Honda, but the way the ECU communicated this to the scan tool was entirely different. Now all the new cars use the same network protocol, so all the communication are standardized and the same.
Also, I think that all cars made for the ’12 model year and after have to have ABS and ESP(Electronic Stability Control) standard. And the NHTSA(National Highway Traffic Safety Administration) is considering whether of not to mandate a Pre-collision braking system. That system would use a laser range finder to determine if a crash is imminent and apply the brakes automatically to prevent a crash.
I’m just waiting until the cars will drive themselves.
Just to add my 2 cents. Most of the police departments are switching to LIDAR. This is basically a laser range finder with the capability to determine speed. The problem with LIDAR is that is it a laser and doesn’t have the same characteristics of RADAR. The beam is very narrow and doesn’t deflect stray signals, so by the time a detector picks up the signal it’s already too late. Normally when a RADAR detector goes off, you are picking up stray signals from another vehicle, not your own. LIDAR is so narrow that most of the time you won’t be able to pick up stray signals and when it does go off it’s because the cop is targeting your vehicle and has got your speed, after that it’s pretty much over. The cop has recorded your speed and there is no time to slow down.
IMHO, just slow down. I did my thesis paper in psychology about the psychology of automobile driving. I forget the math exactly, but it you only drive like 20 miles to work and speed 20 mph over the speed limit, you’re only saving like 5 minutes off your travel time. And some people speed because they have and unfulfilled need for: Fun,Control, Belonging, Assertiveness. Let me point out, that I’m not singling you out. I’m just saying why most people speed.
While watching that video, I also saw another video on why it is impossible on some vehicles. It turns out that on some cars there is a check ball that prevents anything from going down to the tank other than gas. Check out this video: http://youtu.be/k39E2PRofIo
To Zakmartin: I know smoking is bad and I don’t even like the car, but when you smoke in the car it stinks the car up. I’ve been trying to quit off and on. Not smoking in my car is a small battle I’ve won because most people who smoke have to light up in their car. It’s like a habitual ritual. I don’t smoke in my house , so I tend to smoke less in the winter. I’m limiting when and where I can smoke so finally maybe one day I can quit. I know it’s bad but at least I’m not smoking crack, lol.
Hey,
Thanx for everybody’s input. I finally figured it out, it’s just very touchy. But yeah Eric, you are right. Nobody uses the manual on the car brake lathe. I think they just want to teach us the concept of run-out. I talked to my instructor about it and everybody has the model where it automatically sets the run-out.I am currently in a community college auto tech program. The instructors had both the Snap-on and Matco tool representatives come to class and explain the deals. I agree that some of the tools in the list you will not use very often. From what I understand by asking questions, you can mix and match the tools as long as they are in a designated list for the student tool program. I have a lot of tools at home and just took and inventory of all my tools, so I wouldn’t by tools that I already had or didn’t need. Some of the tools that you don’t use all that much can be purchased from a cheaper place and even if they break you can replace them twice before it costs more than a snap-on . Also, the program is a 2 year program and as long as you are enrolled you can get the discount. Some of my classmates wanted to by the tools right away with the financing. Being a lot older than most of them, I told them to wait and save the money then if they wanted to buy the tools they could. At least 5 people have dropped out of the program and it is only the first semester. After 2 years of school some of them might realize that auto tech is something they do not want to do and I’d hate to see them with a bill for tool financing not to mention a tuition bill. As a side note, you can really tell who is paying for the tuition out of pocket and who is paying for the classes with a student loan or with mommy and daddy’s money. Why would you go to school if you don’t give it a 100%. I’m trying to impress my instructors, not pissss them off. What if I need to find a job, do you think they are
going to help me out if I’m goofing off all the time. Do us all a favor and just leave. They don’t leave because daddy has a garage and they have a job waiting for them. Too bad when you work there for a while everybody will think the boss’s son is a complete idiot.