Re: LS1 - Flash - Reprogramming

[Speartech <speartec@iquest.net>]

Andrew, Bob, and others:

After many hours of investigation I am able to reflash the LS1 PCM's with 
an export VIN for my streetrod engines. This allows me to set the engines 
up w/o EGR, cats, A.I.R., or post-cat O2 sensors, which is what most of my 
customers prefer, but it would sure be nice to do much more with the 
calibration!!   I have access to a few of the chips; Intel flash 28fn400 
??......I don't have one in front of me, that is probably not the exact 
number.  What programmer are you using to read these?  It looks like a 44 
pin chip; do they sell an adapter for it, or is it DIY?  Also if someone is 
going to dig deeply into this, I would suggest starting with the 99 and 
newer box.  The 97-98 LS1 PCM was obsolete after 98, while the 99 and up 
covers the Gen 3 truck engines as well as the LS1's. Although I don't know 
for sure I am guessing the new L18 big block (8.1L ,496 C.I.) probably uses 
this same box since it is 24X, SFI, and coil per cylinder like the above 
engines.

		John

>Bob wrote:
>>
>> I have recently gained an interest in having the ability to custom program
>> the LS1 ecm. People are obviously doing it but there doesn't seem to be any
>> "end user tools" yet. Reviewing the list for the last couple of months 
I saw
>> that Andrew K. Mattei was getting into the flash memory of an LS1. Andrew
>> can you tell me where you are with this?
>
>
>I got the chip off the board, put it in the programmer, and read "FF"'s.
>Need to do some troubleshooting on my piggyback board. Those chips are
>VERY fragile, so I hope that I didn't break anything. I don't think I
>did, but still need to do some looking.
>
>> As I understand it the obd2 specification requires encryption of the data
>> going to / coming from the ecm. Has anybody broken this encryption?
>
>
>None of us, AFAIK. Steve Cole, yes. Hypertech, yes. Us (anyone on this
>list, AFAIK), no.
>
>> If the encryption has not been broken that means the flash memory must be
>> accessed directly. From what info I have been able to gather (having not
>> opened an ecm (yet)) the flash memory is surface mount technology. Does 
that
>> mean that the current "turners" are unsoldering, reprogramming, resoldering
>> the surface mount flash memory chip (doesn't sound like fun to me!). Maybe
>> there is some other way, I hope.
>
>
>No, they are not desoldering. I do not see how you could successfully
>remove, program, resolder one of these chips without coming close to
>frequently breaking them. It's that fragile.
>
>> I also see that Steve Cole has this power loader there appears to plug in
>> somewhere. Does anybody know how this works.
>
>
>I've talked to him about it. You tell him what you need for your LS1, he
>ships you a custom program built in to a Powerloader. You plug it in to
>the car, hit a button, and bam, that's it. No options, no reversal. If
>you need something changed, you send him the powerloader, he changes
>stuff, he sends it back, you hit the button, bam. It's programmed. It's
>basically a one-shot device, unless you need a reprogram. It beats
>having the PCM lost in UPS land for days, though.
>
>
>- -Andrew
>- 
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