MAX30102 Not Working — No LED Light, FIFO Stuck at 0x00 (ESP32)

MAX30102 Not Working — No LED Light, FIFO Stuck at 0x00 (ESP32)

Hi everyone,

I’m facing an issue with my MAX30102 PPG Heart Rate & SpO₂ sensor breakout board and would appreciate some help or confirmation if the module might be defective.

Setup:

Microcontroller: ESP32 Dev Board

Connections:

SDA → GPIO 21

SCL → GPIO 22

VIN → 3.3 V

GND → GND

Observations:

I²C scan successfully detects the device at address 0x57, so communication works fine.

Register read/write operations succeed — for example:

LED amplitude registers (0x0C, 0x0D) accept 0x7F

ModeConfig (0x09) accepts 0x07

Problem:

No LED activity: Neither Red nor IR LED lights up (verified visually and via phone camera).

FIFO Write Pointer stays at 0x00 — no samples are generated even with max settings.

Soft reset fails: Reset bit remains set, suggesting the internal state machine isn’t resetting properly.

Supply voltage between 3V3 and GND is around 2.9 V, but the I²C interface still responds correctly.

Likely Cause:

It seems the analog/LED driver section of the MAX30102 is non-functional, while the digital I²C interface still works — possibly a DOA (dead-on-arrival) or burnt module.

Request:

Could anyone confirm if this behavior indicates a damaged LED driver or a fake MAX30102 module (common issue with some boards)?
Any known fixes or verification steps before requesting a replacement would be appreciated.

Thanks in advance for your help!