Okay, after further research here on the forum it appears I can't flash my old T-42 file to a newer module with a different OS. Can anyone offer any options here? Not sure how to find a T-42 module (new) with the older OS on it. Of course, since I have tried to flash the new module (that, when ordered was supposed to be correct for a 2008 Silverado 5.3) they won't take the module back.
Welp... It seems I was wrong about the T42's not having the same risks or restrictions regarding changing the OS. I dug out one I had laying around that came out of an 05 Cobalt and tried flashing a 2007 MY calibration into it using TIS2000 and my Tech2. Seemed to go fine until the end, where I got an error and an option to retry, same error after retrying, and now it seems to be a vegetable.
I think the best suggestion I can offer to get the right module would be to look at the 'SERV NO' on the label and look for one with the same number.
Interesting.... So you read the tune out of your original, SERV NO 242423918052, and that calibration matches what TIS says is correct for your VIN, but the SERV NO for the new module crosses to your truck? When you entered your VIN in TIS, did it ask you for a module part number after you selected the TCM? Sometimes, such as with the LBZ/LMM Duramax, where you could have an A40, A42 or A50 TCM, you get something like this to select the module you're programming:
I'm not sure what happened last time I tried to program the T42, but I was able to recover it with EFILive and its original calibration, and I was just able to flash a 2008 Silverado 5.3 VIN calibration into it with TIS2000. It's possible that the replacement TCM that you have might be able to be programmed with the proper calibration for your truck using TIS2WEB (or TIS2000 depending on when your truck was built).
How does the attached tune look compared to your original tune?
T42_2008Silverado_5.3.ctz/
This is from your tune:
Operating System 24239927 $093DE5E2
System 24240382 $813C37A9
Transmission Operation 24245713 $107A85A7
Transmission Diagnostics 24241986 $AECDB668
This is from the tune I read from my module:
Operating System 24239927 $093DE5E2
System 24240383 $9A3622C3
Transmission Operation 24245712 $3DDEE06B
Transmission Diagnostics 24241986 $AECDB668
The operating systems are the same, of course the serial #, boot block, calibration I.D. and BCC are different.
I see your point, do I have to have a TECH 2 to change the new module to suit my truck?
I'm not positive, but yes, it's possible you might need a tech 2, MDI or MDI 2 and SPS to get the new module properly programmed, unless EFILive can override the mismatch and allow the flash. Hopefully Paul or Ross will chime in.
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