Tim Cook, chief executive officer of Apple Inc., right, speaks with Ryan Tedder, lead singer of One Republic, as other members of the band look on after a product announcement in San Francisco, Sept. 9, 2015. Apple is expected to unveil its iPhone 6s and 6s Plus.David Paul Morris | Bloomberg | Getty ImagesApple announced a service repair program on Friday for some iPhone 6s and iPhone 6s Plus devices to fix a problem that might prevent owners from being able to turn them on. No other iPhones are covered by the program, Apple said in its notice.If your phone is eligible, Apple or one of Apple’s authorized repair shops will repair it free of charge.”Apple has determined that certain iPhone 6s and iPhone 6s Plus devices may not power on due to a component that may fail,” Apple said in the notice. “This issue only affects devices within a limited serial number range that were manufactured between October 2018 to August 2019.”The iPhone 6s was introduced in 2015 and was the second iPhone model to come in two sizes. It’s also the last new iPhone model with a headphone jack. Although Apple stopped selling the iPhone 6S in late 2018, retailers still sold the device.You can check your iPhone’s serial number at Apple’s website.Follow @CNBCtech on Twitter for the latest tech industry news.