I'm kinda getting up to speed on the issues you are having. Did you see the following?
https://forum.hptuners.com/showthrea...e-12200411-PCM
see posts 9, 10, 11, 12 - seems the 1998 f-body PCM was a one year oddball.
So as I understand it, you are trying to use the 2002 411 Blazer PCM in your 1998 LS1 Camaro - probably for 411 tuning purposes. I imagine that should be fine as long as you start with PCM software for a LS1 Camaro with a 411 PCM and wire the PCM accordingly. I found a site that lists the P/Ns for the PCMs and I saw that 2001 Camaro LS1 used the 411 PCM. So I propose that you wire the Blazer 411 PCM like a 2001 Camaro would be, flash it with a 2001 Camaro LS1 OS, and tune away.

To do this, I believe you will need 1998 Camaro LS1 and 2001 Camaro LS1 PCM diagrams. I can supply these so you can see what you have and what you need to do. Can you come up with the 2001 Camaro LS1 software to flash your 411 PCM with?

 

This article claims that the pinouts for the 1999 LS1 PCM are vastly different from the 1998 LS1 PCM and that just plugging a later PCM into the early harness as-is can fry it.
Flash-Based Factory PCMs - Tech - In A Flash - GM High-Tech Performance Magazine
Hope that didn't happen to your 411 PCM.

I'll post the 1998 and 2001 Camaro LS1 pinouts tomorrow morning.

Your profile says you are located in FR. Is that France?

 

sorry for possibly confusing by saying LT1 instead of LS1. I have corrected my posts above.

 

Yes I'm in France (Nantes)
So my story: I've changed the pins of a 98 ls1 pcm TO a 99 pcm using this guide.
https://www.mrk-motorsports.com/stor...8fbodyswapkit/
Now I bought a used 2002 v6 Blazer pcm that I changed the cylinder number, turned off vats etc with hptuners.
The problems it seems to have is that Blazer pcm it's not pinout exactly like a 99 Camaro pcm even that they have the same 411 pcm reference .
I believe (not sure) that I should put a 99 Camaro operating system in the Blazer pcm to work fine.
That will cost me anothers 2 credits.

 

Welcome to the forum. We have a number of Blazer owners from Europe in here!

• It is my understanding that all the 411 PCMs are all P/N 12200411 and all the internal hardware in the PCM is the same on all vehicles.
• I believe the software is specific for both the vehicle and the hardware (PCM).
• The 12200411 PCM was used on the 2001/2002 Camaro LS1 and on the 2001/2002 Blazer (among others). It did not appear until 2001 model year.
• The Blazer is a single coil ignition while LS1 is multiple coil ignition, so obviously hardware pinouts can be directed by the software that is installed.
• The 09354896 PCM was used in 1999 & 2000 Camaro LS1 (possibly 2001 and 2002 as well). It did not appear until the 1999 model year.
• If you flash a 12200411 PCM with a 1999 Camaro LS1 (09354896) tune as you are suggesting, then I'm quite certain you will need to use the pinout diagram for a 09354896 Camaro LS1 PCM and wire it for that vehicle. I do not believe that 2001/2002 LS1 had an EGR valve (and there may even be other differences, even between 1999 and 1998) so there could be minor hardware issues remaining to overcome but it should run.
• I worry that you have bricked your new 411 PCM by hooking up to the wrong wiring. Can you connect to it using HP Tuners still?

I'll post the 1998, 1999, and 2001 Camaro pinouts. That way you can have the pinout comparison for whatever computer software that you end up flashing. The v6 Blazer 411 pinouts I previously posted are irrelevant as you cannot use this software for a LS1 and of course your vehicle is not a Blazer!

What is the purpose of your installing the 411 PCM. How serous is your build?

As I understand it, the 1999+ instrument (gauge) cluster will need to be used whenever you get away from the 1998 Camaro LS1 PCM (which was a one-year PCM).

 

OK - here's all of them. Note that on 1998, C1=RED and C2=Blue. For 1999-up, C1=Blue and C2=RED. Pinouts are completely mixed up and in different connectors between 1998 and 1999. Better I think to buy or find a 1999+ engine wiring harness that will plug into the later PCM and adapt that. It's going to be a big job to straighten your 1998 wiring out to work with a later PCM, but it could be done. I can already see that the 99 PCM does not have the Circuit 400 VSS Signal High (yellow wire at 1998 Red pin 7). I suppose this an example why speedo doesn't work with a 1999 PCM and original 1998 gauge cluster.

 

Thanks
Finally I did a write entire of the Blazer pcm with a 2002 Camaro file and the engine start.
That cost me two more hptuners credits because we put a Camaro vin an calibration in the Blazer pcm.
The problem that I have now is that fans are running all the time. I looked at the engine temperature, fans options with hptuners and I don't see nothing wrong.
But now I should go on a Camaro forum for that 🤪

 

OK - great! Glad things are working out for you. Let me know if you need any more wiring information for Camaro, as I can have that easily. You can PM me here at Blazer Forum. This kind of stuff is interesting to me.

 

End of story. There was a wire that l didn't pin because I had a doubt.
thank you guys
The Blazers have a great pcm 🥳

 

Glad to have helped in some way. Have fun with your Camaro!