Can bus Hacking

dts3

So I'm sitting here in the car right now and I'm not seeing any PID requests come in over CAN. I even did an ECU dump to make sure that I was seeing that traffic in my log and that it wasn't being filtered out. Maybe uprev makes all it's PID requests over K-line?

Data is being logged @ 50hz so the bus isn't being saturated at K-line speeds.

__________________
Visit my blog!
www.LeftoverPi.com

SonicVQ

Wow, that is odd to me....
Are you seeing any CAN Bus activity? I would expect to see activity using service $21 or $22.

How is your CAN bus sniffer set up? Pass through or listen only?
Are your filtering out every CAN ID below 0x700? -OR- just allow -7E0 & 7E8

Since your Z is from 2017, I would be surprised that they would use the slow K-Line.
BUT maybe they are using the K-Line with the NDSIII protocol? I don't know...

SonicVQ

Well... This is VERY interesting. For those interested in making a copy of their ECU ROM, "VQ_Crazy!" on romraider has designed/built/programmed a cheap ($15+) Arduino based, CAN bus hardware solution using the OBD port to copy the ECU ROM to an SD card in 3-4 minutes!

Details are here: https://www.romraider.com/forum/view...p?f=65&t=17089

Just to put this in perspective, this is the first step to being able to tune and update our own ECU ROMs for VERY little money.

I think this will be a good first step to "open source tuning" for the 2008+ (CAN Bus) ECUs.
What do you think?

SonicVQ

I wish I did. There is a little bit of info on RomRaider and I suspect you have already gone through it.

I have not done any disassembly in about 30 years and can only imagine how complex the 32 bit RISC ECU firmware would be.

I think the best starting point is to see if anyone has mapped an HR and use that as a starting point. As time permits, I will try the free version of WinOLS. I hope the learning curve isn't too steep.

dts3

I see full CAN bus activity from the vehicle on all expected IDs. I do not see any CAN activity from Uprev during logging. I DO see CAN bus activity from Uprev:

• When starting Uprev (reading VIN and other data)

• When dumping the ECU

• When checking and clearing code

It's not a filtering issue because I see IDs all the way from 2, to whatever tester IDs Uprev is using (I forget all of them)

As far as reading the bus, I'm using a Vector 1610 with Vector:s CANalyzer software. I can fully interact with the bus and send arbitrary messages.

I'm not familiar with the NDSIII protocol. I have plans to reconfigure my snooping cable to allow me to listen on K-Line also.

__________________
Visit my blog!
www.LeftoverPi.com

dts3

I did see that post before and its interesting for sure. I was thinking about making an add-on board to a RaspberryPI for this, which would be a cool project (I've mad a few add-on "hats" as they call it, it's not too hard). What has kept me from doing that is because I have access to some of the best CAN tools in the industry through my job, so that keeps my motivation for this low.

I post on ROMraider under the name LeftoverPi

__________________
Visit my blog!
www.LeftoverPi.com

dts3

As you suggested I'm sure the 370z ROM format follows the 350 pretty closely. The 370 ROM is 1.5Mb versus 1.0 for the 350. Best case scenario is that it's the same format as the 350s with the HR engine, with an extra .5Mb of unused space. I'd imagine it's more different for the older 350s with the DE engine.

I have the tuner version of Uprev, so I think a good start is to look at the tables that you are allowed to edit, and compare that with what I see in the ROMs disassembly. I can then cross-reference this with what we know about the 350 ROM structure.

Phase 2 would be to make very obvious edits to a table in Uprev (eg setting all values in one table to 3, in the next table to 4, etc). I can then flash and reconstruct the ROM again to see where these known values end up. For phase 2 I'm going to eBay an ECU to do this on the bench; I don't want to do this with my own ECU. If anyone has an extra one sitting around that they can sell for cheap (or donate!) this would would be a good cause!

__________________
Visit my blog!
www.LeftoverPi.com

Elmo370z

Off topic. If successful, could you complete disable vdc?

dts3

Not through Uprev or software like ROMRaider. But you put a switch on the yaw sensor box and turn it off when you want it completely disabled

__________________
Visit my blog!
www.LeftoverPi.com

SonicVQ

I have only looked at a few ROMs, but Nissan seems to move the tables around much more than I would have thought. I'm not sure the 350 ROM definitions will be helpful to find the 370 tables.

Also factor in some CARB/EPA required changes that were mandated around 2012, which may require more program space / ROM.

I know EcuTek creates their own higher resolution tables in different locations than stock, and UpRev might do the same, so please keep this in mind with your testing.


I look forward to your update on the K-Line. Since it runs at 10,400 baud, I guess UpRev could use it and still get a fast sample rate.

HOODEY

Trying to locate DTS