Liquid contact indicator

A liquid contact indicator (LCI) is a small indicator that turns from white into another color, typically red, after contact with water. Those indicators are small stickers that are placed on several points within electronic devices like laptops and smartphones. In case of a defective device, service personnel can check whether the device might have suffered from contact with water. After contact with water, or other liquids, the device is not covered by warranty. Liquid contact indicators are also known by other names such as water damage tape, water damage sticker, water contact indicator tape, liquid submersion indicator.
Purpose.
The main purpose of the liquid contact indicator is to have a lead to the cause of a defect in electronic devices. The LCI can also be used to avoid discussions about liability and warranty, if it is triggered.
Still there can be reasons for doubt.
So, a liquid contact indicator can be triggered, without pointing to liquids causing a defect.
Forgery.
In the simplest form, liquid contact indicators are good for a first lead to the cause of defects. LCIs can be replaced, they are readily available in online electronic stores. But the other interest, use in warranty claims, make them prone to potential misuse. Therefore manufacturers introduced LCIs that are harder to reproduce, even with small holographic details.
Placement.
Liquid contact indicators are placed on several places in electronic devices. For example underneath the keyboard in a notebook and on several places on its mainboard. Sometimes the liquid contact indicators are placed in such a way that they can be inspected from the outside. For instance there is a LCI in the headphone connector, the dock connector, and near the SIM-card slot of an Apple iPhone. In a Samsung Galaxy smartphone there is a LCI underneath the battery cover near the battery contacts.