u/InterestingBunch4220

MAX30102 sensor giving weird voltage readings – turns out the pins are swapped?

I've been trying to test my MAX30102 pulse oximeter sensor to verify my soldering was correct. When I connected jumper wires from my power rails to the VIN and GND columns on my breadboard I was only getting 1.3V at the sensor pins instead of 3.3V.

I assumed my soldering was bad so I redid all the joints and same result. 1.3V everywhere. Checked with a multimeter and it was confirmed.

I decided to swap the power and ground wires around (red to GND, black to VIN) and suddenly I'm getting -3.29V, and if I swap the Multimeter test hands it goes to 3.29 volts and the sensor pins and everything works.

So my questions are:

Is this a known issue with cheap MAX30102 modules?
Do I have a faulty/mislabelled sensor or is this normal?
Is it safe to run it with the wires swapped like this long term?

MAX30102 heart rate sensor, VIN and GND Terminals are swapped