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OBD-II Simulator

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for these 1996+ subies with full standalone engine management systems...those units dont communicate with OBD2 systems...therefore when you take the car to inspection, you fail cuz the obd2 system cant talk to the obd2 system on the car since it doenst exist anymore.


any idea on making a similator box that will talk to the inspection hardware so you can pass these cars?


WJM is creating.

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I'll have to talk to one of my friends...


He's done a couple MS&EDIS jobs, plus, for his Junior & senior Project in college he made a system that reads all the OBD codes and displays the info in neat graphs, etc. I'm not sure if it read OBDI or II though.


Either way, he might be able to work something out that would work for you guys.


Edit: Just talked to him, and :banana:



He thinks it wouldn't be too hard to make a system that interfaces to the MS system to get the tach, temps, O2, etc data, then package it up and simulate the car's ECU.


He believes each brand of car talks a bit differently, but shouldn't be too hard to do. He's been thinking about doing something like this for a while now. He's going to do some more research and let me know what's up.



He's also written a windows application that interfaces to a megajolt board (which I guess is related to MS)


Here's a link to his Senior project board (if you're interested)http://www.cset.oit.edu/stuproj/view_project.aspx?id=9&class=202


however... as to the legality of a system like this.... :-\ I guess it would be like file-sharing programs - it's up to the end user.

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OBD2 or "On Board Diagnostics" 2nd generation is the self diagnostic part of your PCM, or powertrain control module. When the car is working correctly you will not have a check engine light. when you get a check engine light it is because you are out of emissions specs, or you have somthing seriously wrong with your car ie no oil pressure. when an OBDII car is running correctly and your check engine light is not on, you will pass emissions. OBD is designed so that if you do make failing emissions it will throw a code and kick on the light.


To pass an emissions test you need to be able to communicate with the computer so that the computer can give the scanner the all clear. there are two types of codes, ones that are in the recent memory, and ones that are long term, both can be erased by taking off the battery for 15 minutes, but that will throw a new code, which can only go away after you have driven the car for about 100 miles, which theoreticaly is far enough to have any codes come back on that you may have tried to erase for passing emissions purposes. so in effect, you won't pass emissions if you just disconected your battery recently.

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