I fixed one again.

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Took a week. Parasitic draw on a newer Cadillac. People couldn't fix. Not even the dealer. Going from car, to internet blogs, sites, and identifix. Nothing. From car to wiring diagrams, to graphing meter. Nothing. From car to scan tool. Analyzing 20 codes in 30 or so modules. Found the big draw the first day. Amplifier, and radio. Nope! Not it. Took the trunk panels, rear deck, rear seat, radio, a few plastic covers, just to access modules that were integrated into the radio-on star-antenna-tv-cell phone-voice activation-steering wheel buttoned-fancy thingamadoodadstufandallthatjazz. Nothing. What the heck is going on with this overengineered, american, german, mexican, pile of wires, plastic, and tin anyways. Okay. Time to think outside the box, and make new. Get out the graphing meter. Time to poke wires some more, and recheck everything. Maybe I missed something. No short to grounds, modules active, and will not fall asleep. Hmm??? No accessory wires going to modules, radio, and amp anymore??? Hmmm??? Well look at that! My graphing meter is reading binary code on the communication data line. That is how they turn on the amp, radio, and modules now. Ok. Find all data communication splices, and unplug them. There should only be about 50 wires to isolate!! !! Found the little bugger. Traced it down. Well wouldn't you know. The radio, and the amp uses the most power in the car when they are active. Causing a parasitic draw, and killing the battery, due to a module that is sending data communication to every module, activating all of them, because it will not fall asleep like it is supposed to, and probably believes there is a problem ( I wish I knew the language). The solution??? None other than... the right rear door module. Soo, long story short. I new age car technology. Radio=door. Boy, that was easy.

Control of a car is done via the CAN bus - there are two of them in most cars, a "high speed" bus that connects the ECU to modules in the engine, power steering, ABS, etc (this is the bus that your scan tool connects to via the OBD port). The second bus connects door locks, power mirrors, radio, digital HVAC controls, etc. Lots is possible by hacking around on these busses.

More info if you're interested: http://www.canbushack.com/blog/index.php

I will poke around on that site thanks. Two CAN bus lines go into the amp, and radio on that car. it is redundant too, in the sence that it runs in, and out. OBDII data link is one wire, and it is all redundant. It goes everywhere on that particular car. Newer stuff I have not had to deal with yet. 2007 CTS. I use an autel and it is a good scan tool with alot of functions especially for the price. it has limited programming capabilities, and some useful O.E. stuff in it for about 50 manufacturers. could not pick up any faults in the rear door module. it just said modules were active. I did a ping on everyone i could too, and they all worked. The dealer did not catch it either. They make things complicated, so I cannot fix it, and they can. But they are wrong. Because I did. And they did not. They are out smarting themselves.

There are open source drivers out there which will enable you to connect your to the computer via the CAN bus lines. This blog has several neat examples of how you hack a Volvo S80: http://hackingvolvo.blogspot.no/2012/11 ... n-bus.html

I really have no need to hack a Volvo. As a matter of factly, I wouldnt mind ever working on one ever again. I'm too american, it must be a stigma. I can think of a few more from over there too. . I do like that S4, but that is about it. I have an autel, identifix, and a vantage-pro. That always seems to get me by. That guy was talking about a diesel heater? We just burn gas, and install a remote start. there is a smart phone app for most 2014's too. As far as programming goes, I wouldnt mind getting hondata for my k-20 si. And a g-reddy torbo kit. . Someday maybe.