I would like to be able to do 0411(p01) and p59 pcms. I would be interested to know how you do it in 15 mins?
I would like to be able to do 0411(p01) and p59 pcms. I would be interested to know how you do it in 15 mins?
I first desolder the flash chip, then overwrite the whole flash with a stock tune using a universal programmer. Last step is to solder the chip back to the PCM
Doing this you can read and write as usual.
I have a lot of practice soldering electronics, for an untrained individual it may take longer than 15 min. If you have no experience with this kind of work you can easily damage the PCM
How much would this equipment cost starting from scratch? Not the solution I had in mind but something to consider.
Like $150 for the programmer with the adapter plus the hot air station
I am very new to obd2 stuff, so what do yall mean when you say its locked? I have never heard of this before. I have seen several tuning threads in this section but never saw anyone mention unlocking a pcm first.
79 Jeep Cherokee, AMC 401, T-18 manual trans, hydroboost, 16197427 MPFI system---the toy
93 Jeep YJ Wrangler, 4.0L, 5 speed, 8.8 rear, homebrew hub conversion and big brakes, hydroboost, 2.5in OME lift, 31x10.50's---the daily driver
99 Jeep WJ Grand Cherokee limited, 4.0L, auto, 2wd, leather and power everything, 99% stock---the long distance highway ride.
EFILive, HPTuners, and various handheld tuners modify the seed/key as a way of locking the pcm. I am not sure exactly what they do, I think it changes the location the data is stored at. When I try to access it with software I do have it shows finding the original seed but key it generates does not match. I have been able to put together that key algorithm for ls pcms is:
KEY = 934D - SwapHiLo(Seed)
So the formula goes like this
SEED = 0A69
KEY = 934D - SwapHiLo(SEED)
KEY = 934D - SwapHiLo(0A69)
KEY = 934D - 690A
KEY = 2A43
If resulting number is negative, use 1934d.
http://www.miniwebtool.com/hex-calculator/
it does not modify anything when just reading a ecm out. edit. I reread what you wrote. I see what your saying, just not how I would word it.
The ecm sends a seed, and you must reply with the correct key.
There are 256 seed/key combinations plus a few extra orphans as I understand it. There will be a tool like antus's released soon that will do 411's, and if the dev can find the time, many more GM ecms
Bookmarks