I'm in the USA and the post pertains to PCM. So I think I'm in the correct section.
Let me just tell you I have a working PCM. All I'm trying to do is disable "Vats".
My scanner: OBDX Pro/VX is all up to date with Drivers and firmware.
I'm using a bench harnss.
Below is my GM Black Box PCM and information tag. This is what I'm getting when I check properties and write pcm on Pcm Hammer.
I tried it with OBDX Pro VX Com3 and with OBDX Pro VX - J2534 Device. Got the same result on both.
I only saved the OBDX Pro VX - J2534 Device
Properties
[12:38:50:467] PCM Hammer 021
[12:38:50:473] Tuesday, May 19 2026 @12:38:50:47
[12:38:50:475] Initializing J2534 Device
[12:38:50:480] Loaded DLL
[12:38:50:548] Connected to the device.
[12:38:50:562] Battery Voltage is: 12.901
[12:38:50:567] Thanks for using PCM Hammer.
[12:39:04:545] VIN: 1GCEK19R0XR144774
[12:39:04:569] OS ID: 9365085
[12:39:04:572] Hardware Type: P01_P59
[12:39:24:746] Calibration ID query failed: Error (This is a problem line)
[12:39:24:767] Hardware ID: 872432205
[12:39:24:841] Serial Number query failed: UnexpectedResponse (This is a problem line)
[12:39:24:869] Broad Cast Code: CMUF
[12:39:24:890] MEC: 0
Write pcm
[12:34:41:929] PCM Hammer 021
[12:34:41:931] Tuesday, May 19 2026 @12:34:41:93
[12:34:41:932] Initializing J2534 Device
[12:34:41:933] Loaded DLL
[12:34:41:986] Connected to the device.
[12:34:41:990] Battery Voltage is: 13.01
[12:34:46:552] VIN: 1GCEK19R0XR144774
[12:34:46:576] OS ID: 9365085
[12:34:46:580] Hardware Type: P01_P59
[12:35:06:772] Calibration ID query failed: Error
[12:35:06:799] Hardware ID: 872432205
[12:35:06:874] Serial Number query failed: UnexpectedResponse
[12:35:06:901] Broad Cast Code: CMUF
[12:35:06:923] MEC: 0
[12:36:53:825] Will save to C:\Users\Garcia-1\Desktop\Defaut Bin Files\test J2534.bin
[12:37:03:839] Querying operating system of current PCM.
[12:37:03:872] OSID: 9365085
[12:37:03:944] The PCM didn't accept the unlock key value
[12:37:08:993] Unlock response truncated, expected 6 bytes, got 4 bytes. (This is a problem line)
[12:37:08:995] Unable to process unlock response.
[12:37:08:997] Unlock was not successful.
I checked this post by Antus:
viewtopic.php?t=8613
Found this :
Please disconnect USB, disconnect OBDII, disconnect battery (remove all power), and turn off ignition switch for 1 minute or more (I like to reboot my PC as well, then everything is in a known state), then,
1. Connect Battery.
2. Connect OBDII
. . Wait for VCI to fully boot
4. Connect USB.
5. Start PcmHammer.
5.a. Select Device if needed.
6. Turn Ignition on.
7. Select 'Read Entire PCM' from the Tools menu.
Waiting 5 or 10 seconds between steps does not hurt!
And found this:
$10_brute_unlock_var_algo.zip
Here is where you all come in "What can I do to get a pcm write
I have more questions but I'll stop here for now...
Thanks for any help you can give me.
In case you haven't figured it out yet I'm a complete NOOB when it comes to PCM HACKING.
