8746 $61
(im using a friends burner and I have 1 whole spare chip to use right now)

Ok so, Ive been meaning to install the 5-spd .bin since I swapped over from the auto for awhile now, finally got around to doing that.. I decided to also throw in the rev limit patch since it looked easy to accomplish so I did that as well, and set the limit at 2000rpm to make sure it was working..

So I took the .bin I found online, patched, disabled vats for now until I know what freq to put in the new bin (i think those need changing?), changed rev limit, other then that just saved the bin and burned it, and it verified ok, even downloaded the bin off of it and compared it and was indentical.

Threw it in the car, got fast flashing SES light. Double checked to make sure it was in right, was fine, pulled it out and put it back a few times to make sure connections were ok, same thing still. Threw old chip in, worked fine.. Decided based on some of the things I read here I would try disabling the checksum by using 'AA' for the prom id (correct?) to rule out that it was miscalculated somehow? Thats all I changed for the 2nd burn. Put that in today and it worked, no flashing SES, and starts and seems to drive fine.. the "throttle follower" I believe it is, seems even more annoying then it used to be.. but otherwise working.

However the rev limit code doesnt seem to be doing anything, I thought perhaps I used the wrong .bin and it wasnt patched but if I use the difference tool in TunerPro the fuel cutoff values are different, and the values at 06F3 and 06F4 which from what I understand is what should have been changed, are different from my original unpatched version..

Since I have limited burn time right now I thought I would get some ideas on what I might be doing wrong.. thanks in advance

edit: If i understand the patch code right its supposed to only change 06F3 to $1B and mine ended up as $D1 and it changed 06F4 to $1B *confusion*

 

What is the 4 letter BCC of the PROM you started with? The reason I ask is that the rev limit and forced knock bypass patches only work with the early '8746 BINs. This is something that I recently discovered, that GM changed the code.

The patches work with the ANLU and ANTT BCCs. And probably others in that series.

The patches do not work with the AX series of BINs. This includes AXKT, AXKS, AXKU, and AXKW. And proabably others.

As for the rev limit patch it will patch in 2 bytes. At 06F3 and 06F4. If your BIN wasn't already $D1 at 06F3, then the patch won't work. The change at 06F4 from $30 to $1B is what makes the patch rev limit instead of speed limit.


Needing to change the maskid to $AA means that the BIN didn't have the checksum updated.

I am working on a second set of patches for the newer $61 code base. The forced knock was easy, just move it. But the speed limiter code was completely changed. They even put additional calibration parameters mixed in with the code. And did some other funny things.

RBob.

 

yes I downloaded the AXKW bin and went with that.. damn GM and there funny business..

Do you think thats why I had flashing SES, because of the speed limit code being.. broken after I patched it?

Is it possible todo some kind of Mass copy of all the calibration parameters from my newer bin to the older version, and then patch that instead?

 

Well I gave that a try and got my answer (copying all the calibration values into the older bin, then patching that and setting rpm limit, saving file, burning etc)
The answer was fast flashing SES light again ;0
Any way I can calculate the checksum myself to make sure its getting adjusted correctly? I get the feeling thats not really the problem, didnt try burning it with the checksum disabled this time though.