No — iPhones do not include a usable, disabled FM radio that can simply be switched on. Older models had combo chips with FM capability, but Apple never wired the antenna/tuning/audio paths, and newer models (iPhone 7 and later) lack FM support entirely according to Apple.[3][5][6][7]
Some early iPhones used Broadcom/Qualcomm combo chips that included an FM receiver core as part of the package, which led to the misconception that FM was merely “turned off.” However, the FM-related pins weren’t connected inside the phone—there was no antenna input, no tuning lines, and no audio routing—so the device never functioned as an FM receiver.[6][8][3]
Apple has stated that iPhone 7, iPhone 8, iPhone X and later do not have FM radio capability in hardware and therefore cannot enable it via software. This position was reiterated during public calls to “turn on” FM for emergency use, emphasizing that the necessary hardware simply isn’t present in these models.[5][7][6]