338S00839 Charging IC (Tigris) for iPhone 14 Series, 99 Pin (U4000)

One documented iPhone 14 Pro Max repair began with a missing 5 V USB rail and ended with charging restored after replacing the charging IC at U4000. That chip is the 338S00839, the 99-pin Tigris charging IC for the iPhone 14, 14 Plus, 14 Pro and 14 Pro Max.

The listing describes it as OEM New Grade.

Signs of a Tigris fault

• No charging from cable or pad.

• Missing USB voltage on the board.

• Intermittent charging.

• Fault after a bad charger.

Diagnosis

Start with the cable, the port and a known-good battery. Measure 5 V at the input capacitor; if it's present and the battery still doesn't charge, U4000 is a likely suspect. Check the boot capacitor on the charger output in diode mode too, since a matching reading on both sides points to a fault.

The board is stacked, so separate it before preheating. Lift U4000, clean the pads and fit the replacement on fresh flux. Test cable and wireless charging, and leave the phone on charge long enough to see steady progress.