What Is an LDI?
Liquid Damage Indicator — the sticker inside your phone that turns red when water has entered.
Definition: An LDI (Liquid Damage Indicator) is a small adhesive sticker placed inside a phone during manufacturing that changes colour — from white or silver to red or pink — on contact with liquid. Every iPhone and Android phone contains at least one LDI. Technicians check it first when diagnosing a phone with suspected water damage.
Where the LDI is located
iPhone: Inside the SIM card tray slot — visible without opening the phone by shining a light into the slot.
Samsung Galaxy: Also inside the SIM tray slot on most models.
Internal LDIs: Additional LDIs are placed on the logic board, charging port area, and near the battery connector — only visible when the phone is opened for repair.
What a triggered LDI means
A triggered (red/pink) LDI confirms that liquid has entered the phone. Apple and Samsung both use LDI status to determine warranty eligibility — a triggered LDI voids the manufacturer warranty, even if the phone appears to be working normally. It does not tell technicians how much liquid entered, which components are affected, or how severe the damage is — that requires opening the phone and inspecting the board.
Related terms
→ Water Damage — what the triggered LDI indicates has occurred
→ Corrosion — the ongoing damage a triggered LDI points to
→ IP Rating — even IP68 phones can have a triggered LDI
→ Ultrasonic Cleaner — the treatment used after LDI confirms water damage
LDI triggered on your phone?
PhoneDoctor treats water-damaged phones with ultrasonic cleaning — same day. Don’t wait for corrosion to spread.