The dealer should not have to flash your PCM to pull up codes. And, if there is an ABS code, it may not show on the Gryphon because the Gryphon doesn't show ALL the various codes for non-driveline related subsystems.
But, if a flash is deemed necessary, I think I'd want to have it done, even if it meant rewriting your tunes.
- Jack
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2024 F150 Platinum SCrew 3.5L PowerBoost FX4, Peragon Tonneau Cover, LineX Bed, 35% Window Tint on All Sides and Rear, Full Nose Paint Protection Film, Husky Mud Guards, Lasfit Floor Liners, VIOFO Dash Cam