I've been working on this for more hours than I would like to admit... hoping I could resolve it without having to post. I have also spent quite a bit of time talking and messaging with my brother, who has experience flashing SMECs often, and no luck. So on with the posting-

Hoping to not overwrite this, I'm going to start by throwing out the ingredients I've been working with:
-Flashable SBEC#1 (done by Rob a long time ago, has his cal pre-loaded, runs when installed)
-Flashable SBEC#2 (one of the last done by Rob, no cal pre-loaded)
-BoostButton cable (older version- has the 2010 board)
-BoostButton cable (also one of the last, 2013 board Rev.3)

Two functioning SBEC Turbo harnesses:
- 1991 that doesn't have any known issues, runs a 2.2 8 valve, manual
- 1991 2.5TI, hasn't been thoroughly tested, runs a 2.5 8 valve/manual

Windows 10 laptop
Windows xp laptop

Me: less hair and higher blood pressure than when I started


Both cables pass the com test. Both cables can trigger actuator tests through MPScan.

I have attempted flashing to SBEC#2 in both vehicles. I'm have a jumper wire to send 12V to the bootstrap wire of the cables and I release the contact after a second. I get a variety of errors: "unable to download entire boot program for serial coms", some messages showing bytes received, sometimes something like "bootstrap program corrupted".

I try to read the cal on SBEC#1 with the same communication errors.

I'm starting to think more that there is something wrong with the program itself. There are times after a few errors, I will click on the flash button and it goes directly to a "write error" message without even showing the prompt to prepare to boot power the chip. It is doing this on both laptops. So far I have only tested the XP laptop on the 2.2 vehicle.

This is driving me nuts! Any help will be greatly appreciated.

Here is that last com log I had from the Windows 10 laptop
*****************
-Comport analysis for mptune version 2.0.6.2
-Locating ports on computer-
name:USB Serial Port (COM3) deviceid:FTDIBUS\VID_0403+PID_6001+BB1NSB9AA\0000
number of ftdi devices found - 1
ftdi port num:COM3 serial num:BB1NSB9A
Inverted tx:True Inverted rx:True
Vcp driver loaded:True
Latency is set to:16
checking to see if usb port number COM3 is a moates device
Moates device not located on this port
default com port set to:COM3
*********************

It sets the latency itself at 16. I have also attempted setting it at 2 with the same results.