Snapon Diagnostics Product Forums Diagnostic Home . Diagnostic Product Index . Customer Care        
Diagnostic SoftwareDiagnostic PlatformsAsk-a-Tech, Automotive Repair InformationTech Central
Go Back   Snapon Diagnostics Product Forums > Snap-on Diagnostic Products > Diagnostic Platforms > J2534 (Flash Reprogramming) User Forum
Home Today's Posts Register Members List FAQ
Thank you for visiting Snap-on Diagnostics Product Forums.
You are currently NOT logged in to a registered account. Some functions of Snap-on Diagnostics Product Forums will not be available to you if your are not logged in as a registered member. For a limited time only, registrationto Snap-on Diagnostics Product Forums to Snap-on Diagnostics Product Forums is !! FREE !! Select the    **REGISTER NOW**    link to register for your FREE Snap-on Diagnostics Product Forums account!!

Thread Tools Display Modes
Old 03-26-2021, 08:05 AM
greasybob's Avatar
greasybob greasybob is offline
Senior Member
Join Date: May 2008
Location: wisconsin
Posts: 1,587
greasybob You made it!  You've done a great job ofearning reputation from your peers.  You now have secret access to a new hidden forum!


I'm kind of a sucker for the hard jobs. Should be able to do anything a dealer can do with the right tools. Most flashes go with out issues, used stuff is always a gamble. I just want to know if GM changed anything that would not allow the VIN to be re written or if any one else has seen this happen.
Reply With Quote
Old 03-26-2021, 10:58 PM
Speedybon's Avatar
Speedybon Speedybon is offline
Junior Member
Join Date: Jan 2012
Posts: 22
Speedybon Congratulations!  Your peers have given you enough reputation to put you into the fist level!


You will probably lose money on programming. We would build the car to show all options and download it with too an SD card. Some would take hours. Not a money maker. I would stay away from Radio programming.
Reply With Quote
Old 03-27-2021, 11:06 AM
Glide Glide is offline
Senior Member
Join Date: Jan 2015
Posts: 303
Glide Made it to level 2!  Looks like you are on your way to becoming famous


As I said,I haven't tried a used Nav radio in a GM,but I found this info in service information "
It is critical to use the service replacement Communication Interface Module only in the vehicle for which it was ordered "
Another part of SI refers to the Nav radio as the communication interface.So maybe a new Nav radio has the VIN written to it before it is shipped to the dealer.
Reply With Quote
Old 03-30-2021, 08:45 AM
SnapOnKid's Avatar
SnapOnKid SnapOnKid is offline
Senior Member
Join Date: Jan 2011
Location: SoCal
Posts: 865
SnapOnKid You made it!  You've done a great job ofearning reputation from your peers.  You now have secret access to a new hidden forum!


I have not done a used Nav that new. The one I did do,

I Tried reprogramming the software and It went through the entire process and said it failed near the end. I was thinking either the radio was messed up or maybe there was something else that needed to be done and there was a super secret trick that was not being esplained...

On the normal radios, I have to reprogram the software in order for the new vin to be learned and for it to unlock. Sometimes a standard vin reprogram will take and sometimes it will not but even when it does take usually the Radio remains locked. When I reprogram the software it seems to overwrite the vin and unlock it every time.

The 2nd time I tried to just re-write the vin. I verified by scanning the radio again and looking for the vin. When I cycled the Key, the nav unit came to life and was fully functional. I was in disbelieve... When I scanned the car again it had the correct matching vin.

I used a Genuine Tech 2 and used it as a passthrough when attempting to program.
But The Vin Unlock portion for the nav radio was in the scan tool and not the SPS subscription.
Reply With Quote
Old 04-14-2021, 08:53 AM
Nate75 Nate75 is offline
Junior Member
Join Date: Jan 2019
Location: leonard TX
Posts: 11
Nate75 Made it to level 2!  Looks like you are on your way to becoming famous


after 2010 almost all GM vehicles wil not allow the vin to be changed in any module. I have tried several and ended up opening the radio up and swapping the smaller board that doesn't have the vin in it and it resolved the issues. there are systems out there to connect directly to the PROM chip and reprogram the vin, but I have not tried them.

Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -7. The time now is 12:41 AM.

Reminder: Your participation in these areas of the site is solely at your own risk. The
information is only the opinion of the poster, is no substitute for your own research,
and should not be relied upon for business critical decisions or any other purpose.
Never assume that you are anonymous and cannot be identified by your posts.
We reserve the right to discontinue any users' use of any such public forum
for any reason. Please read the Terms of Service.

Snap-on is a trademark, registered in the United States and other countries, of Snap-on Incorporated. Other marks are marks of their respective holders.
2023 Snap-on Incorporated. All rights reserved.