Hi @armelynhuldong, After some digging online I managed to find an English copy of the service manual (link) for the Siaretron 4000. It has a section on calibration, and the references to what information is relevant to the flow valve calibration can be found on page 77. The manual doesn’t have a section on damages via rust, and the section on replacement parents only offers the typical “only use OEM parts”. Additionally If the rust has only damaged the support brackets for the sensors, you might be okay. However, if the sensors themselves or any connections between them and the other boards have been damaged then that could be the cause of the issue. If the problems are due to rust damage, then you may have to find replacement parts or go to an authorised service technician (as much as I hate to say this, there isn’t any detail on how to source parts from their website so it might be pretty locked down). I hope this helps.
You should normally be able to restart by holding the home and power button (on the right side) at the same time. In your situation, since either the power button or home button or both are stuck or broken, your best way forwards is probably a recovery tool or just waiting for the battery to die, and then restarting it by connecting it to power. Update (03/05/2023): @joanabumere It’s also a stretch, but there are potential issues with memory corruption if you weren’t updated to the latest version of iOS (Apple released another set of security updates to iOS 12 a few months ago to provide patches to older devices such as the 6s). It’s definitely worth connecting your phone to a computer with iTunes installed (works with both Mac and PC) using a Lightning (iPhone charging port) to USB (standard port on computers) cable and then seeing if an update is available or it wants to enter recovery. If nothing comes up in iTunes when connected or linking to the device is not an option, you’re probably going to want a...