Procedure for dealer interaction

[MQ105]

If a trip to the dealer is necessary for some reason, what is the procedure regarding EFI? Does the truck need to be returned to stock? I am not speaking about warranty issues, although that may be a concern to some. What would happen if the dealer updates the ECM or needs to hook up a Starscan for diagnosis, brake bleeding, etc? For that matter, can a Starscan or the like be used to make a change (enable power seats or fog lights, for example) with an EFI tune loaded?

Thanks

[GMPX]

If the dealer updates the ECM then your tune will be wiped, other than that having an ECM with an EFILive tune won't stop normal dealership diagnostics.