A Brick?

[custodian]

I have a 2001 0411 PCM from a 2500HD. It has been programmed at one time and has been locked and have been unable to read it, write to it, etc. PCM Hammer shows that it cannot unlock because it needs 6 bytes and only receives 4. If this PCM can't be opened, is there anything inside salvageable?

[B52Bombardier1]

Hello Bill,

There is a You Tube video that shows the path to possibly unbricking it. You will need to remove the lid to find a point on the printed circuit board that needs to be grounded at the instant of powering up the PCM. This gives you about 15 seconds for PCM Hammer or LS Droid to load the kernel to then take control of the PCM. After that, you should be able to load the 12212156 or any other 512k byte OS and bring it back from the dead.

Edit: Try the picture.

Rick

[custodian]

Hello Bill,

There is a You Tube video that shows the path to possibly unbricking it. You will need to remove the lid to find a point on the printed circuit board that needs to be grounded at the instant of powering up the PCM. This gives you about 15 seconds for PCM Hammer or LS Droid to load the kernel to then take control of the PCM. After that, you should be able to load the 12212156 or any other 512k byte OS and bring it back from the dead.

Edit: Try the picture.

Rick

These are pictures of an 00-02 PCM and a 03-up PCM. A slight difference where the arrow points to, but would most likely be the same point to ground.

The left photo is the 00-02 The right photo is the 03-up.

20210510_180849[1].jpg20210510_180856[1].jpg

[custodian]

Hello Bill,

There is a You Tube video that shows the path to possibly unbricking it. You will need to remove the lid to find a point on the printed circuit board that needs to be grounded at the instant of powering up the PCM. This gives you about 15 seconds for PCM Hammer or LS Droid to load the kernel to then take control of the PCM. After that, you should be able to load the 12212156 or any other 512k byte OS and bring it back from the dead.

Edit: Try the picture.

Rick

I now have an unbricked and unlocked PCM. I turned everything on, used PCM Hammer, I put electrical tape around the pin I needed to use to make sure I didn't touch another pin, took a piece of wire and grounded it to the frame of the PCM and then the pin, and then flashed it, Now this took a couple of tries, but I got it done. I used the system that I'm using on the 5.3 that I'll be installing in my 73 C10. I was also able to read it with another tuning software now, which I couldn't before. I'll post some pics.

20210512_102711[1].jpg

20210512_104450[1].jpg

20210512_110041[1].jpg

20210512_110240[1].jpg

[B52Bombardier1]

Hello Bill,

Its great that you have kept another one from becoming a book end, door stop or wheel chock!!

Rick

[custodian]

Hello Bill,

Its great that you have kept another one from becoming a book end, door stop or wheel chock!!

Rick

Thanks for the picture and info.

[custodian]

I bought another 411 PCM, it didn't have the service type stickers on it. I was able to read the PCM, got the OS number 12216125 and Hardware number 9386530. I saved the file, and now I'm unable to read or do anything, LOCKED. Now my question: I'm going to attempt another save, can I use the OS number 12212156 when I try to reflash or should I just use the original OS?