Engine Perf 2 Test 2 Network Basics

I guess a little case studies every now then from I did it fixed and I like to really share these things because they’re their instructional this particular one was a 2008 suzuki xl7 limited 3.6 liter v6 mfi dohc engine designation in 36 a 66,000 miles check engine light was on with a heated oxygen sensor circuit and sufficient activity bank 2 sensor to code Pete Oh 160 replaced the downstream oxygen sensor on the rats out of the engine which would be the firewall side you know the bulkhead side and the code returned the oxygen sensor bank 2 sensor to was sitting at Point 45 volts and didn’t change bank 1 centuries between 0 point 6 and point 7 volts so what happened this is important bingo it says bank 2 is the left radiator side of the engine you know left being the radiator side verify the correct oxygen sensors are placed the confirmed fix was to replace the wrong heated oxygen sensor and replace their own sensory yep the early was I tell you what when they first came out with bank one sensor one at bank one sensor two and Bank 26 or two it makes do you know sister once I did that I’ve changed her own or thunderbird because I was confused about where the sensors work what don’t understand why you’re standing here I mean do you have a clearly defined objective out there or something you know is all in silver going to see them not this insane yeah balance and rotate so name one cylinder one side hold a cylinder one side wherever so under one is before they had and sent it to his Africa you know and then name to do sighs Chester one is in front of the casket sure who’s behind the cat so you’re never going to have a bank one name two on a force of it no now sometimes you will believe it or not on a straight six it’s kind of crazy yeah they split the flooding the rear cylinders I mean it finds three of the back three and like on a Jeep Cherokee like the later model ones you’ll have two oxygen sensors and language it’s like two banks pretty interesting here’s another one 2008 chevy silverado 2500 HD LTZ 6-litre v8 multi fuel injection OHV vnk you know what’s a four-wheel-drive obviously the anti-lock brake system in red warning lat are all our own all the time okay there’s no communication with the electronic brake control module the engine control module is putting out yoooo 121 and you owe 137 au codes or network codes right okay body control module diagnostic trouble codes is you Oh 121 yoooo 137 and you to own and then which you to own an N is a manufacturer specific code because it doesn’t start with a0 alright so what he did was he turned the key off you check the resistance between pin 6 and 14 of the data link connector the correct value will be 60 homes because you got the terminating resistors in there that’s telling you the network’s get all the way and there’s any broken wire any of you check in on the two sides of the network and it doesn’t have a 60 on now you do ya hook the battery before you do this right okay you turn it if it’s okay you turn the key on engine off check the voltage jump in nineteen is a lot blue wire voltage should be near battery voltage to this is not going to mean anything to you unless you know which way are you talking about if no voltage you present check connector X 1 26 pin see serial communication enable circuit is number 59 th repairs electronic brake control module data wiring the enable surgically repaired so basically there was some wiring problems on that one okay the reason I’m going through this is some of the stuff is network-related where we talked about that work today and so got a common mental instruct the well it needs to be done before lunch you know before lunch i oh god yeah he knocked it out it’ll be fine 2009 mercedes-benz c300 4matic sport 3-liter v6 mfi dohc engine designation they didn’t have that 270 2948 miles it’s got a bosch you mean 9.7 naturally aspirated flex 228 horsepower sixty thousand eight hundred twenty-one miles the tire pressure monitor system lat was on okay so first the adjusted tire inflation on cold tires recommended pressure listed on the gas filler plow where the ignition switch own use the left frat arrow buttons on the steering wheel the select service press the down arrow buttons select tire pressure and then press ok tire pressure monitor active is now displayed press the down arrow button and use current pressures as new reference values press ok to confirm will be displayed press the ok button to confirm and so basically this had to reset those the tech tech tip is if winter temperatures drop below freezing set the tire pressures at least two to three PSI higher than recommended reading on the fuel filler flap that’s where it is on this particular mercedes is on the fuel filler when you open it up because your tire pressure typically

where the tire pressures found in the door usually if you will a sum up will be on the vin sticker and some of them may have a sticker separate sticker and now have seen them build in the right hand rear passenger door it’s just crazy they kind of stick them in there any other seems to me like I’m is important is that they put a word but he could find them real easy to be a standard location right okay so let’s say here’s one right here 2006 GMC envoy XL denali 5338 m fi OHV biniam 180,000 miles the delay windshield wipers aren’t working the vehicle equipped with rain sense system on the windshield so if it rains a little bit of iridescent change because of the water on windshield it kicks the whopper genre brand water on the windshield does not make the wipers work you disconnect the rain central and windshield see if the delay functions network if they do verify powering round of the rain sensor and replace the sensor if still no operation check the wiper switch input the motor confirm that lay signal the wiper motor is present and the problem with that one was wiring from the rain sensor apparently to the modular shop when the rain sensors unplug the wipers default to normal operation based on wiper switch input so if you’ve got a rain a sense whopper problem by a train since y % and disconnected and the last one last but not least 2006 kia optima l x 2.7 liter v6 mfi dohc VN for 87,000 well the engine runs good at at all but when you’re driving down the road is start to buck and the engine control module shuts down injector number to think about this now we’re talking engine performance here the actual camshaft position on bank 2 is minus 22 minus 25 degrees at apple and owned bank one is 122 degrees well I’ve doesn’t sound right the desire don’t both banks is 0 degrees and that’ll see any time you’re looking at scan tool you’re going to look at the desired target for something whatever you’re looking at and then you’re going to the actual if the desire to the actual don’t match you got issues you gotta go find out why they don’t match can it do anything like a conference at idle speed 11 you can actually go on a Chrysler and I’ve got a sheet on that and you go in there and you can select your idle air control and you can target you can say I want it to go to 1500 rpm if it can’t get to 1500 rpm then you need to clean some passages or you know replaces whatever I mean that’s basically what they’re looking at here and so you notice this guy’s looking for the target too obviously they’re out there all night here ok so the engine runs rough when the all control valve is energized all control valve is what I actually changes the cam timing on those is because it’s got you know Oh slow noi does that its energy I it returns to normal when it’s de-energized when you d energize it you know it changes the weight run the same on both banks with it oh C V energized bank to go to forty percent and bank one goes to fifty percent it sets a bank to correlation code p 0 0 18 and i miss go do 30 too that’s why I shut down injector number two because the number two is Miss pirate as the cylinder is misfiring on the newer cars and shuts an injector down to keep the raw gas from getting to the converter and burning it up okay disconnect the battery touching cables together for at least two minutes not the battery now you don’t a shorter battery like a welding machine you don’t actually touch the cables together right for about two minutes so reset the engine control model and see if don’t see a actual camshaft position reading goes back to normal that’s an easy enough thing to do in it let’s do a cheap and easy first let’s go do the expensive complicated stuff you know let’s don’t throw 1400 on our module on it and find out we could have done something cheap and easy and fix it right don’t pull the heads until you put a thermostat in it to make sure that’s what you know it’s not a reef different reason okay alright so if it does the camshaft timing we haven’t stuck advanced at some point and the ECM may have learned the position that normal position is 0 degrees C it’s kinda like your throttle position sensor when you turn the key on it looks at whatever the throttle position sensor sitting on and it calls that Idol that’s why you’re not supposed to touch the gas when you’re starting these newer engines if you touch the gas it’s going to get a false reading for idle and it’s going to make it do things they make it hun all this kinda stuff ok say it will think that whenever it stuck to make the valve timing advance went back to normal it takes time is driving the vehicle and verify the missus going if the camshaft timing is still reach our is cope the bank to camshaft position sensor and the crank sensor or a dual trace to check the phasing in quality of the signal scope bank one to compare you’re going to compare the banks to each other because like a tutor for centuries you see them adaptive memory camshaft timing clearing a CSF memory so anyway those were little case studies right they’re really good oh all he did well that one there a good way to start is to go ahead and just pull the battery cables touch the terminals together and see if the Union and all these dodge vans or says we’re talking to URI electronics this time I’ve got a video on my youtube channel about a dodge 2005 dodge caravan ahead in here that the whenever you went to the door locks would work you hit your

fob they would do anything get your buns in the doors they would do anything you get a scan tool you plug it in plug the scan tool in you go into the body computer on that thing you’re going to look at your data you’re looking at inputs and outputs alright so when you look at your inputs you could push push the lock buttons and the body controller was reading the buttons and then you try to go in there and do an active command mode luck with your Genesis not the Nemesis because it will do that and then you tell them to lock in a lot of it or they wouldn’t unlock and lock and unlock it unlock authority because so then I pull the battery terminals off text them together let it clear out all the capacitors will have everything out I don’t forget everything it knew when I pull up front put it back on there won’t forget door locks yeah and that’s all it was for the reset its kind of reboot your computer because you got a little micro processors in there anyway see what I’m saying now one down there with this guy that worked for the sony plant that when a sony plant was still an operation over when they remain all that magnetic tape everything and even to having an eagle premiere which was you know with all due respect we were the dealer for that car but it was a mistake to be drowned an eagle premiere okay so we pulled up whenever he first came in there the whole thing on the deck is monitored the checks all your systems and he sees if your lats are working here on all that it was jumbled head bunch of gibberish on it and so I got it I reached you know he’s that Nash panel back whenever I had that little 100-dollar box that’s cutting live and unplugged it plugged it back in we had normal operation just reboot the computer sometimes take care of it okay so I said if it does it again we can have one of these things so came back about a week later and all I did again so elsewhere one 100 bucks so this thing right here even with the lights and all that our own there’s some really delicate little lap bulbs that were snapped into the cluster behind the printable area you know the pr in dl area a lot of even we do on the last own can now unbeknownst to me at that time if you wiggle those a little bit with a key own it would cause them to blow we’re just really sensitive i didn’t know this you know at the time I’ve never seen that my life work on a car if you jiggle a bulb it blows it mean please you know what’s wrong with this so anyway that was granted you know it was so he gets it back and he says hey this ladder here to work anymore because the ostensibly I did every thank you anything I did so they give it to another mechanic tanisha the woman phone replaced those bulb is gonna be forty dollars or whatever like yeah well this guy you know he was a oriental guy so he goes in there he said no mr. Marshall couch in there the were all sitting there talking together and he starts talking smack about the you know we don’t have that problem with Japanese cars and this is blah blah blah and all that kind of thing and so I figured I was gonna zing him you know think why not you know already thing real fix his car anyway so I said we were a little box it was in a dash that I had to change out because all gibberish and everything he was yeah I said that was made in Japan oh how did you know whatever we fixed this car anything in charge anything but it was kind of funny to watch you I don’t know what this means whenever you do this and beat your head between your hands with us what you did one said that all right let’s start out with this one here now that our prodigal children or their okay we’re going to get technician a says module this is injured performers to test two okay we’ve burned the first 13 minutes talking about case studies which they missed it we’re really important technician I says the module communications networks yeah are you coming here come here come here come here what’s up bro oh you gotta take care of that yeah well what I’ll need to do is put the parts in so you go into class and then whenever I get out of here I’ll do it then you can go ahead here take that basically your copy anyway but when i when i get that done how long it just check back with me in about an hour no just leave me here lootera food he shot over their part I’ll incorrect okay mention that to Zack catch the guy with the glasses yeah all right technician aces module communications networks are used to reduce the number of wires in a vehicle technician visa is communication network is used to share data from sensors which can be used by many different modules who’s right about that huh what do you think what up below if you’re going to buy go communication networking actually reduce the number of wires in the car because you got a sensor sharing data you know whether like for instance there was times whenever you have a output speed sensor that was going up here and it was talking to one box then you’d have a sensor in the rear end it was talking to another box and so now once they do is they take any lock or wheel speed sensors and I let the anti-lock brake module run that up to the instrument cluster the engine controller and all that so it’s basically it’s the little Network thing instead of having a hardwired to help with your modules you guys guys though the differ between

serial and parallel interface what’s the difference way serial and parallel interface yeah did you not burn that in well yes and no what serial interface is basically going to be where a lot of stuff goes over two hours a lot of different signals comes over a couple of large parallel interface is like on your engine controller you know you like 104 wires that’s a parallel interface is also got a serial interface you know some serial interface item that comes off of that but serial interfaces basically when the computers got to sort out the signals because they’re all coming on the same line you know like on your USB port you know you can plug into the USB port and get all kinds of dad over just a couple of wires at USB port there’s forward newest before two of them provide power and ground and the other two basically provides Adam and all kinds of Stephanie over the left well although years ago when i first started all this probably went in a networking they would have all these separate wires each one I’m going to the computer and it would rain each wire separately so you have a lot of worries you have enough wires to choke a horse in here no all right so anyway let’s move on to your module a module is also known as a what a resistor pack of terminator a node or a bus it’s basically a nude a high-speed canvas communicates with it scan tool through which terminals 6 and 14 6 and 14 s Toby yeah 16 is power and four and five aground on a 16-pin you know dlc can you remember that sixteen is power I mean six days and will power up your scan tool for and fiber ground in your scan tool if you if you ever have a scan tool that you plug it in and it won’t boot up with no power get your test line and see if n 16 is hot and that’s the one will know I come 16 if you get your skin to look like this yes my that 16 is the one that’s right here don’t you got basically eight terminals in here and that isn’t quite draw that long enough you know to 12 three four five six I need to draw up smaller one two three four five six seven eight and then you’ve got to appear their land up perfectly with those in for it fives will be those two is sixteen is going out that’s Universal on every data link connector pretty much the other stuff is you know there’s some other pins that are assigned for the you know different kinds of communication but basically there is actually a little thing i can give you on that and i’ll give it to you if I don’t forget okay uart uses a signal it toggles between zero volts and what and 0 15 is that wrap it right around up there you like that there are five those work for you works for me their own fab looks good that is a one of the networks and that typically General Motors some of the earlier motor stuff used your coke I’ve also got General Motors always use a class to network you know what i mean so you guys met work stuff is kind of weird if you’re not used to it I want to reboot this machine well now don’t go too all right bit anyway that’s alright this keyboard I haven’t changed out two keyboards day and if it is unplug of ps2 keyboard and plug it back in you got any change feelin for ya do that I want to do the forced second salute to shut it down and then bring it back up all right now it’s like the next one GM class to communications toggles between what that’s number 50 and 70 and seven that is be 0 7 now this is almost like an automotive electronics test piston engine performance test you know tune something all right so which terminal or data link connector does general motors used for class to communication that’s a good question in it is to be a good memory GM outland which is local area network is the general motors term for which type of module communication I think that’s going to be si si high speed can cans control area network can H and can L operate how what you got with that that’s going to be d all of the above can h is it to an ad volts we’re not transmitting can H goes to three and a half volts when transmitting KL is at 2.5 volts about pulse when not transmitting and they got high low speed can buses the can bus is that are the fastest ones that I know about or like 500 kilobits per second make sure you remember that that’s kilobits per second and not kilobytes per second because they kilobytes per second or multiplying it by a factor of eight anytime you’re talking about you know the speed of your internet or whatever you’re taller your Lin or your your network card that’s kilobits as thousands of bits okay so

what’s a bit anybody know what a bit is here you go whispers your 8-bit makes it like this second-rate amateur looking left the wrong place he plugged it into the he plugged it into the place where the mouse was supposed to go okay so anyway I’m gonna shut it down again and really bring it up all right now let me see so make sure you’re understand that can the high-speed can operate at 500 kilobits per second and that’s the one that’s used for what what’s your most critical functions on the car that has to have the fastest communication to systems particularly well engine control and anti-lock brakes you know vehicle dynamics stuff he’s got out of that now the other stuff like your audio system and all that kind of stuff is talking over a slower bus it’s like you know like instead of being 500 kilobits per second it’s 80 / so you know what I mean so all right so we’re we go soon number 9 which terminal of the obd2 data link connector is a signal ground for all vehicles you know there’s actually a single around and then there’s a you know another ground so basically you’re eliminated d that’s the signal around before is also a ground but it’s not a single ground terminal 16 of the obd2 to data link connector is used for what Alex 12 volts positive that be number 10 okay technician a says that a breakout box Bob can be used to access the bus terminals when a scan tool are used to activate the modules now there is a breakout box believe it or not just just for your data link little breakout box that you plug in it’s got a little place where you can plug your scan tool and it’s got another thing it plugs into the data link and it’s got little test points on it so you can and it’s got a number so when you plug it in you can actually drag it out in your lap and you can check you to a little test once you get your scope you can actually connect your scope to the ones are your buses own and you can watch the activity on there you know and see what’s going on I’ve actually been to a situation one time where I had a there was a 1997’s court and the lady come in and she says her you know it has a network on it you know as believe it or not it was obd2 and this thing she was grumbling and complaining because it wouldn’t speedometer didn’t work in the transmission wouldn’t shift now one of those do have to do with each other and the idea a good plan speed sensor that the output speed sensor wasn’t given any you know information to the PCM if it doesn’t know the vehicle move it is not hold shift is it it’s called staying low gear basically hasn’t got electronic transmission the transmission with a 480 and it’s got four solenoids in it they’re hardwired to ground as PCM puts power out to it which is kind of backward from what we’re used to anyway the long way short of it is the gap up to speed sensor on there seemed to work ok when he test drove it she didn’t get out of the parking lot on it before its design you blew it he’s like it move it as whole people as product under say whatever you didn’t fix it if they just like it was you were to say that you like it would you like it if you unless you’ve ever worked on anybody’s car you don’t say that but they just say that just farmers particularly so anyway so she go back in and then they call for take a 40 but what that means they gave it to me you know if they want to make sure that it’s a one-stop shopping they throw it to me and that’s kind of pressure you know I’m saying because she’s all hot bothered and irritated so anyway i plugged in my scan tool sure us but I wonder what transmission will shift new speed sensor right in there plug the scan tool in wouldn’t talk hmm what scan to and talk strange scans who would boot up but it wouldn’t talk so I said well I need to my scope up to the standard corporate protocol wires and see if I’m getting any activity there so I have a fresco puff and I’m getting activity well there’s activity on the network I’m not talking with skin too and it all turned out that one of those grounds four or five whichever when it was for a thing her five whatever anyway was going out here to the battery and it’s sort of like there was a battery terminal was made and it had this whole thing it plugged in as a whole bunch of grounds it plugged in with you know silly little swag and extra battery and they got all chalky an old like batteries do get all that stuff and then lost that ground connection and battery engine would run everything was fabulous can’t do it talks but I’m didn’t worked one shift hey whatever I’m speedometer makes your signals making it was then turn now that ground and took everything down and so basically I cut that off of there slaughtered a terminal there you know I hadn’t needed like four

wires to go to them grounds and I put four little wires in there and then I saw their dim and heat shrink tone all that kind of stuff and then she was good to go and no more troubles that was sort of a bad way to do that anyway ok so it see the thing about it is even though I showed network activity with my scope I still wasn’t getting any speedometer activity I wouldn’t get any transmission shift I mean that ground was confident all the little things and sometimes if you got a bunch of stuff it’s not working the smartest thing you can do is find out what that stuff has in common is it got grounds incumbents got connectors and Commons and got positive income or there’s all that stuff getting a signal from the same module you know this kind of thing okay now we’re gonna do here technician ASA is a breakout box blah never finish that question can be used access the bus terminals well scan tools used activate the modules cognition be says a 38 cavity diagnostic connector found on many BMW and Mercedes vehicles under the hood which technician is correct about that SC basically fact I was working in a Volkswagen dealership you know they have just stopped using this one little central data link connector the Volkswagen had put under there you know their engine compartment where you plug this machine in and basically all the machine was doing was asking you yes or no and we had a similar thing like that on results and jeeps the earlier jeeps and it had you know two different wire terminals under the hood if we’re out beside each other you plug biscuit this ms 1700 scan tool thing in and a little clamshell box ahead a little screen that spell across there and blue you know LCD letters I mean LED and so you’d say here and say okay you plug it in and ahead yes and no buttons and it would ask you a question and you would check whatever it said and you put yes and ask you another question you put no yes no yes no why you’re making text knurling and if it did if it didn’t come to an answer it would give you a message it said engine fail to start if you mechanical or ignition problems but you knew that you know and that made you want to just throw the machine in the trash and you know whatever the process of sending multiple signals of information the same time over a single wire and then separate the signals is receiving in is called what what do you call that guy’s multiplexing that’s a good answer low speed networks operate and less than how many bits per second that’s a third to me it pays that’s a low speed network and is operating in less than ten thousand bits per second all right the UART data bus operates at a baud rate of how many bits per second 8192 the SLO speed network okay which of these commonly designated d to be is an optical bus system connecting audio-video computer and telephone components in a single ring structure with a speed of up to five thousand six to five million six hundred thousand bits per second you got that SC actually domestic digital bus that sounds really official in it which terminal of the you obd2 data link connector is the chassis ground for all vehicles alright we’ve already talked about five being a signal around we know for in fast ground so they’re only one web trap that’s got to be be this could be for an obd1 ford is able to provide engine serial data if there are terminals and which cavities at the DLC and the DLC on those old Forge’s under the hood the escort has serial data that funko does not the escorts at 94 the Broncos in 89 got me that’s I mean our trailer perjure okay so which cavities are the DLC that’s number 17 this be one time let me pause for a second to tell you this story this is engine performance anyway I wouldn’t just drop by the dealership to see nothing when I was off on friday or whatever and he’s over there any cuz i’ve got this van in here it has been fat and i’m in fact this thing for a week and when i crank it up it puffs out a bunch of black smoke it runs really rich and all that kind of stuff in them the fuel pressure is okay and i can’t really figure out what’s going on with it i really ticked off and i just wish i had serial data and I grabbed the you know the connector where you plug the scan tool in and the wires for cereal that over there nasty you got cereal that on this thing it was one of those where it could be either one I even wrote about this a little bit of a facebook technical writer page have you guys are like my technical writer page have you like that give you my technical writer Facebook page is actually I tell stories and stuff on their diagnostic stories at all well long short of a lot of people I got 90 something likes on it and everything so anyway I’m sitting here and I told him I said you got data stream he said well I plugged the scan tool and it told me I didn’t have data stream and I says well tell it you’ve got an e 40 d transmission because you know when they Reaper top the program for that they added dentistry he says this one doesn’t have any for only transmit he’s got a OD I said it don’t matter last to it until it you got any 40 D and then the scan to let you see your data stream and so he went in there and trap that sure enough he a dentistry because I’m kicking myself I had no idea I can do this and I

said well now let’s go in here see what your problem is but that gum 500 other control he had is only Metro Doreen’s older hundred I’ll report it was terrible but see when i backtracked I realized how I don’t off target on that thing and so anyway let me see your let’s see which of the which of these is a version of bite flight and a high-speed serial communication system rental vehicle network a flex right bus be domestic digital by see GM land or D can Network which one is that that’s going to be a flex rape us sound like template calls up nowadays on it or science fiction a single wire serial communication protocol it uses one master control module and many slave modules is called what that’s actually a see that is a motorola inter correct interconnect mi technician a says a candy module will flash the red LED rapidly if communication is detected technician be says a twisted pair of wires is where two hours are twisted to prevent electromagnetic radiation from affecting the signals passing through the wires that’s actually be candy module you know that’s an old GM stuff to that candy stuff and I’ll tell you something else they do they actually foul up and give you all different kinds of silly acronyms for these networks you know the Chrysler had a one wire network on a PC apolis rat and so the pci bus was a thing let’s see programmable component interface i think it was and the other the pci that you see in some of your desktop computer or other stuff is peripheral component erase so if you see pc at or candy or something like that that doesn’t always stand for the same thing and if you’re talking about it on cars then you know the candy bus is something you know GM used long time ago technician a says Chrysler obd1 which is 81 to 95 vehicles or equipped with a bus system called serial communications interface technician be says craft or programmable controller interface yeah that’s what I just saw pc at is a three-wire that’s actually a one wire so that’s not rat and let me mention this network thing while we’re here Chrysler also called there they had a bus that was called up a ccd but you may read about that if you’re doing some diagnosis or coal chute that stands for Chrysler collision detection and wine assembly only call it at is because it’s tied into the airbag somehow knew basically what that means is all these signals that are on this wire can be sorted out so that the signals did you know these packets of information can crash into one another well like this here prevents that it actually keeps them from doing that imagine I you know the if you’ve got a serial like I was telling before let’s say a serial communication is when everybody is on a two-lane highway and they have to get off wherever they need to go right and the parallel communication is like you’ve got 40 lanes and everybody is driving side by side and they’re going to the same destination you got me and it’s now that that’s the difference between the give you a memory bug so you can remember the different serial communication and parallel communication all right is that in the last question that y’all had yeah all right we’re good to go rat ya know the answer to that will be was wrong basically 2188 was right people wrong pci is a single earth I tell you something else to the one on the one of the forge that shows the pin 7 I think it’s blue with the white strap it’s a one wire bus to so these buses you got to be able to talk I’ve got an entire study in there if you guys don’t flip through it on network buses it was up by Bill Fulton and I wound up I went to that class up there while I was it the mac revision I’ve got it a book a book in there on my best it’s got all that you can flip through it learn a lot of stuff just looking through a little book that’s the only copy of it I’ve got but not want to flip through that and read this till this network stuff is pretty doggone interesting stuff and the important thing you need to do is find out who’s on what network and who’s not talking and if you’ve got a whole network down let’s say that you got a bunch of modules on one network and that whole neck of the network’s down you’re gonna make sure you go through to unplug those module one at the time until and when the network comes back on land you’ll find out that module you unplug goes well had it pull down then your place that module I mean you know a lot of stuff like that it’s you got to do all these newer cars