This may be sort of a noob question, but is there a black box on my EVO?
I don't necessarily want it known how my car is being driven, or if certain parameters are being tweaked-not that I'm planning to do any such thing

Those with knowledge, help a brotha out!

 

the ecu may record the last few moments before your car crashes...so they say

 

Say? It does. Telemetry data is always maintained for 5 seconds, and it stops recording the instant your airbags fire.

The purpose was for early airbag deployments to help determine their effectiveness. They're still in there for that purpose, but now they have a dual role in busting reckless drivers.

 

GM cars have a lot more big brother features than the standard ECU's, do a search on google.

 

Its worth noting also, that any condition that causes the check engine light to come on takes a snapshot of various sensors as well.

I had a high speed misfire once that caused the check engine light to show - the dealer reported that it occured at 87 mph/3700 rpm, engine temp, etc...

just something to be aware of...

cheers.

 

and the easy way arround it, if do something stupid id to disconnect your battery.....

 

Its not very complex, but there is snapshot data captured when the check engine light goes on.. Depending on the circumstances the data may be useful or not.. However if the airbags are deployed, that would trigger a check engine light, and it will capture a snapshot.

I also notice on occasion that there's snapshot data in entry "0" that doesnt correlate to any sort of CEL, its not there all the time, but its there.

Safest thing to do is clear codes before taking it in for service.. Obviously if you can, read the codes and see if their is anything wrong.. then clear it.

It wouldn't surprise me that there's more information stored in there that isn't documented, however there doesn't appear to be any sort of perminent memory and if you disconnect the battery for some time (longer than 10 minutes or so) it should be long enough to clear everything.

There doesn't appear to be any flash memory (rewritable memory that doesn't require power) in this ECU besides the Flashable EEPROM memory (used for fuel/timing tables, trims and operating parameters)

Therefore disconnecting the battery for a period of time should clear it.

What is interesting is in any serious accident, its likely the battery cables will be cut or it will lose the charge... so its likely the data would be lost anyway.

The **ONLY** thing I've noticed that is unusual is the ECU for the airbags.. It has several inputs that I cannot determine what they do.. One is the vehicle speed sensor, there are several impact sensors, but there also appears to be a TPS input and a few others.. if any data is retained, I'd suspect it would be in that box.

There is NO data on it, and therefore I haven't been able to extract any information without disassembling the device, and I don't have a spare one to reverse engineer.

 

guess if ur in a series accident.. the dealer wont really need to troubleshoot..since ur evo would most likely be trashed..

 

Yep, but the importance of the data would be in forensics.. Especially when fatalities are involved and fault needs to be determined. Obviously if the car is obliterated they can generally tell how fast a car was travelling.. but if they snapshot the speed and other data, they can likely use that against (or for) the person driving..

But yeah, if the car is destroyed, its unlikely that data would be useful for a service department...

I really doubt there's anything all that complex in the car.. the only thing I can think of that would have that info is the airbag ECU since it does need impact information and vehicle speed information to determine whether or not it should be deployed.

 

I beg to differ. There is a backup battery internal to EDU, per the schematics. So the question is what memory does it maintain when the car's batteyr is disconnected.