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jfpilla
June 16th, 2004, 05:47 AM
I've read in a number of posts in other forums that HP Tuner has a recovery feature.
Is this so or is it a misunderstanding of how it works?
LS1 Edit will fail for various reasons and a rewrite or pulling fuses will correct it.
How will Flashscan compare to these two editors regarding "Recovery"?
Can a PCM be fried with these editors for any reason?

Dirk Diggler
June 16th, 2004, 06:41 AM
http://www.efilive.com/forum/viewtopic.php?t=578

Blacky
June 16th, 2004, 07:35 AM
There are two ways to reflash the PCM:
1. Reflash the entire flash memory including operating system and calibrations.
2. Reflash only the calibrations.

Option 1 has the potential to render a PCM inoperable and non-reflashable, that is what people call "fried". There is nothing physically wrong with the PCM, it's just that the "program" inside the PCM is either non-functional and/or no longer communicating with any off-board reflash tools.
The only way to recover the PCM in this situation is to desolder the flash chip, program it using a chip programmer and resolder the flash chip to the PCM. Not something the average DIY tuner is prepared to do.

Option 2 does not alter the PCM's operating system (program code), so no matter how many times this type of reflash fails, the PCM will still continue to communicate with the off-board reflash tool. That means, the off-board reflash tool can restart the flash (as many times as is necessary) until a successful reflash is completed. I guess one could call this recovery.

Regards
Paul

jfpilla
June 16th, 2004, 08:18 AM
So I guess Flashscan will reflash only the calibrations. That's very nice. Thanks Dirk and Paul.

Dirk Diggler
June 16th, 2004, 10:36 AM
There are two ways to reflash the PCM:
1. Reflash the entire flash memory including operating system and calibrations.

Option 1 has the potential to render a PCM inoperable and non-reflashable, that is what people call "fried". There is nothing physically wrong with the PCM, it's just that the "program" inside the PCM is either non-functional and/or no longer communicating with any off-board reflash tools.
The only way to recover the PCM in this situation is to desolder the flash chip, program it using a chip programmer and resolder the flash chip to the PCM. Not something the average DIY tuner is prepared to do.


Regards
Paul

As a developer this is the dumbest shit i have ever heard of why do extra work that you dont have to (reading the whole 512) just read what you need to read and leave all that other shit alone ESPECIALLY volitle data. I also think this was planned only because every pcm that is killed because of an OS requires you to send carputing another 200.00 to add another license that is the only reason i can think of doint shit the long way. There is more things to mess up doing it this way. And as volitle as Windows is why would you even risk this? Corner the market maybe?

Highlander
June 16th, 2004, 11:30 AM
ANother probability is because having the complete file will let you identify it easier and more compatible with other things...

GMPX
June 16th, 2004, 02:14 PM
As a developer this is the dumbest shit i have ever heard of why do extra work that you dont have to (reading the whole 512) just read what you need to read and leave all that other shit alone ESPECIALLY volitle data. I also think this was planned only because every pcm that is killed because of an OS requires you to send carputing another 200.00 to add another license that is the only reason i can think of doint shit the long way. There is more things to mess up doing it this way. And as volitle as Windows is why would you even risk this? Corner the market maybe?

Dirk, LS1Edit 'reads' the entire 512K as there is some important info in there that is not in the calibrations area.
However, they do only reflash the calibrations area, leaving the Operating System alone, they 'should' be able to restore a PCM as the PCM is still able to communicate (slightly more limited) when just the calibrations have been wiped.

deezel
June 17th, 2004, 10:20 PM
Dirk, LS1Edit 'reads' the entire 512K as there is some important info in there that is not in the calibrations area.
However, they do only reflash the calibrations area, leaving the Operating System alone, they 'should' be able to restore a PCM as the PCM is still able to communicate (slightly more limited) when just the calibrations have been wiped.

So does this mean its just a matter of knowing how to properly communicate with a confused PCM?

GMPX
June 17th, 2004, 11:10 PM
So does this mean its just a matter of knowing how to properly communicate with a confused PCM?

Well, yeah.

The only way you can kill them to the point of needing to pull the chip off is if some important comms routines at the very start of the Flash get wiped, that will only happen if you are programming the cals 'and' the Operating System, like what GM would do, and yes, Tech2 does kill them every now and then.

Dirk Diggler
June 18th, 2004, 12:39 AM
All the dealers i took them to said they couldnt flash it because the PCM refused to communicate with the Tech2

GMPX
June 18th, 2004, 01:46 AM
All the dealers i took them to said they couldnt flash it because the PCM refused to communicate with the Tech2

It depends on the security level of the Tech2, the issue is you can't extract the VIN from the PCM with the 'normal' commands when it is in a semi operational state. Most dealership setups require the VIN, cal part numbers etc to be pulled from the PCM before reprogramming can occur, mainly to protect against people flashing say a truck file into a C5 etc. I'd suggest this was the problem.

Dirk Diggler
June 18th, 2004, 02:52 AM
All the dealers i took them to said they couldnt flash it because the PCM refused to communicate with the Tech2

It depends on the security level of the Tech2, the issue is you can't extract the VIN from the PCM with the 'normal' commands when it is in a semi operational state. Most dealership setups require the VIN, cal part numbers etc to be pulled from the PCM before reprogramming can occur, mainly to protect against people flashing say a truck file into a C5 etc. I'd suggest this was the problem.

Good infomration as of this morning it is all history. I bought a new one from the dealer and returned the other paper weight as a core. I will be up and running today. Only think that bugs the bejesus out of me is it wont have a tune and i refuse to send the dark side anymore money to add another lecense