Okay, I already count this as a loss but more or less I need to see if this has happened to anyone else.  I will break it down in the steps it happened to try and make sense of what happened.  Hopefully if a root cause is isolated others can avoid wasting boxes...  lengthy but i want to explain what happened.

I was editing 2.7t M-box code for my car, I messed with KFMI_UM, corrected CS with the MTX plugin through tuner-pro as always.  It gave confirmation as always and thats when the weirdness started.

So generally when i shut down tunerpro out of habit i will hit save on the file again then close the bin and close the program, what caught me as odd was that once again it said CS corrected, even though it should have given the message that no changes were made and that no CS were corrected since had just saved it previously.  That threw a small red flag, so I closed tunerpro and re-opened it.  Same thing.

So i sent the file over to my other laptop, same thing.  Just kept calculating CS at save which wasnt huge cause for alarm to me, just odd.

I put it into me7check and EcuFix, both reported it as good.

I flashed it with the nef tool, uneventful, completed, disconnected, great.

I go to do a TB adaptation and clear codes, cannot connect to the ecu through VCDS, cannot connect through nef, start trying every tool ive got, no connections.

Pull ecu, reset power, reconnect and attempt to reflash with nef, I can connect but cannot do anything.  Cannot get boot mode.

I notice the throttle is cycling over and over, every second, non stop if the key was on.  On a whim I decide to try and crank it over since at this point im thinking the ecu is toast anyway.  To my surprise it fires up, runs for 3 seconds and dies.  I do this 2 more times and then try to connect again hoping maybe i had reset whatever the hang up was, nope.   Decide I am done messing with it and go grab another ECU.  As I pull out this troubled one its hot, it smells... I let the smoke out.

But how?

I changed the file back the the last known good version.  I edited KFMI_UM back to stock and the CS issue stopped and everything still appeared normal.  Flashed that to a new box, everything went normal and car was back to life.

So in the end I guess I am just curious WTF just happened.  Did editing that one map really cause all this or was it a fluke?  I have killed ecus with bad checksums and grounds undone, but never like this.

Edit: added 3 files, one normal, one with just one line of KFMI_UM edited which causes the tuner pro CS save glitch like yesterday and another that is a problem file that has been run through winols instead.

From my experience with the MTX plugin is that it has issues when you edit certain TQ variables... It says the CS is corrected, but in reality it is not correct.

I always double check with OLS after editing w/ TunerPro & MTX CS PLugin and when TQ variables are edited OLS will find that the CS is incorrect and correct them.

I've bricked my ECU a few times on the road due to this until I realized what was happening.

Wasnt fully smoking but def hot and had the distinct smell.  This only came after i tried to start it up.

On the TQ maps and CS, wouldnt me7check or ecufix (whittakers) catch that?

I am going to mod the file back and try to replicate the CS save issue then send it over.

I have winols also, but never use it.

I had an ecu recently that was stuck in a programming loop. No matter how many times you flashed or reset the power it would always read THIS IS THE RAM PROGRAM with vcds. Not that it's relevant, but it was curious nonetheless.

Are you talking about that other multipoint block you found? If so, ME7Check doesnt check it!

I get that whenever a flash fails, or if i dont hit disconnect on the older versions of nef.  I am always able to connect with VCDS and see that message and then re-flash.  Not this time though


I just got done changing the file back to how it was yesterday when this happened and once again tuner pro is doing the same thing, ecufix and me7 check say its good.

Need to reinstall winols real quick to test.

No idea, I didnt open the case but i smelled totally smoked which would be totally new to me for a CS error.

I think there is more too it with the TQ maps