RomRaider

Hi there. I have a USDM 2006 Subaru Forester XT 5mt. The car has been modified (some CELs disabled) but I am unsure what I can safely flash onto the ECU to revert it to a factory image. It has the stock EJ255 block + heads, but few mods that I want to tune it for.

My main issue with the ECU is- I cannot find the ECU ID anywhere. My ECU ID is A8DH102I. I can find A8DH100I, and A8DH101I, but no A8DH102I. My binaries come out as 4212585206.bin and everybody else's come out at 4212585106.bin. I have also seen 4212585006.bin.

I am confused as why this is, because I can't find anyone else online with A8DH102I. My car was definitely returned to stock before I purchased it, so maybe it was reflashed to stock by a dealership to the "latest" version? That is my main question- are the numbres at the end essentially a versioning system, ie- 100, 101, 102.

I played around with my ecu_defs.xml and did Find & Replace "A8DH101I" with "A8DH102I". This allowed me to connect to my ECU and provided full extended parameters, which are all seemingly functional and accurate. I am able to read learning table values, see individual cylinder roughness monitors, et cetera without a problem. So the memory locations are all the same between "A8DH101I" and "A8DH102I".

I downloaded somebody's stock A8DH101I ROM and pulled my car's ROM and I did a comparison. Lots of things changed. Some of this is necessary, but some of this concerns me. I will make a separate post under this with photos and explanations.

Would really appreciate an expert's opinion on this as I have never ran into a situation like this before. All the tables "make sense", but I don't want to modify it and risk bricking my ECU if the memory locations somehow aren't the same.

Attached is an image showing the comparison between my image and the image I can find online for my car.

Lots of things changed that need to be (secondary air system is removed from my car) but confused why P0340 is straight up missing from my image. Too many other differences to list and my car should be stock. The tgv butterfly valves are removed, but the rods, motors, and actuators are all still there. So although it's not hurting anybody having those codes disabled, there is no reason for it.

This screenshot showcases a weird difference between my ECU (left, 4212585206) and the one suggested online for my car (right, 4212585106). It seems like my ECU is using relative values for all the tables, but the one I found online using absolute values for all the tables. Mine seems weird. When I have seen other people tuning OS, it typically seems like the values are absolute. This could also be because I couldn't get a proper ECU definitions file and ROMRaider is interpreting this incorrectly.

Here is a better list of all the differences. I will pay anybody to help me, unfortunately I think I need a veteran's assistance. I work as an electrical engineer, so I have a bit of embedded systems knowledge, and I stick close to Dominic Acia, who has taught me a lot of what I know about Subaru. If I can learn about this and figure it out, I will give back in any way I can to help the OS community.

The table locations in your rom are different to the rom that the def was meant for. Changing the CAL ID and ECU ID in the defs to your IDs loads the rom but the table locations are incorrect.

Looks like there is a suitable definition available over here:
viewtopic.php?f=8&t=16583&p=148083&hilit=A8DH102I#p148083

I see, interesting that an 02 WRX and 06 Forester would share the same ECU? Seems really odd to me... but you are right, it did work and fix the values.

So I'd like to revert the tune to a stock image, but on https://www.romraider.com/forum/viewtopic.php?f=35&t=7591 all I am finding is 4212585006 and 4212585106. My ECU reports the ECU ID as 4212585206.

Are CAL IDs and ECU IDs tied together? (Ie- can I upload a stock "older version" like 4212585106 to my ECU since I cannot find 4212585206 anywhere?

both your boost tables there are relative PSI, the reason one seems different I think it's because you're viewing it in rom compare and it's showing you the difference between the two roms not the roms actual value if you don't use the rom compare and just look at the two roms how do the values look?

as for rom compatibility yes if your current rom is A8DH102I then usually that means you can flash back to A8DH100I or A8DH101I as in most cases that's how subaru releases the revisions. You can do a compare and a test flash before committing if the first few blocks match up OK on the test then at least if you do run into a problem you can flash back to your previous rom without getting the soldering iron out.

I see what you mean. I don't think both my boost tables are relative. But yes you would be correct. Here are some photos explaining/proving this. Not sure how I didn't make this connection earlier. Whoops...


as for rom compatibility yes if your current rom is A8DH102I then usually that means you can flash back to A8DH100I or A8DH101I as in most cases that's how subaru releases the revisions. You can do a compare and a test flash before committing if the first few blocks match up OK on the test then at least if you do run into a problem you can flash back to your previous rom without getting the soldering iron out.[/quote]

This is great to know. So if I flashed 4212585106.bin onto my ecu, would my CAL ID then change to A8DH101I instead of A8DH102I? I always thought A8DH101I was some kind of hardware revision, which is why I feared flashing the wrong binaries to my ecu. I have no problem running an older version of the ROM if it means I can be sure I am stock.

I guess it would be helpful to have a definition of "CAL ID" and "ECU ID"

Really appreciate the responses everyone.

If having more parameters in the logger would help you, send me your logger def to try something.

For my logging parameters- all I did was take the standard logger xml, Find & Replace all instances of A8DH101I with A8DH102I. Too big for me to upload, but you can download the standard one from here and make the change yourself.

That unlocked access to extended parameters such as individual cylinder roughness, FLKC, FBKC, knock sum, et cetera.

What other parameters are you talking about?

yeah that's it if you flash the A8DH101I rom then your ecuID/calID will be A8DH101I in romraider logger. looking at your boost target there and the tables that have been changed i'd imagine someones done a bit of tuning on your rom.