I set up a simple test of a 1602A LCD display. It is connected to a esp32 board, SCL - 4, SDA - 5. I ran the I2C_scanner and serial monitor reported up to six different addresses. It's been running for a few minutes and now addresses are down to three: 0x01 0x27 0x3C. Nothing else is connected and I've tested with 3.3V and 5V. The default address should be 0x27. Where do the other addresses come from?
what LCD? With an expander? Which one?
Link the product(s).
Link the datasheet of your product.
Post a picture of your hardware setup.
I suspect that it is the ESP32 which is most important.
Also remember that ESP32 is a 3.3V device. I2C pullups should pull up to 3.3V and not 5V.
Start by being sure your clock rate is in the range of the display, the ESPs can go very fast. Second be sure the pull up resistors are installed properly, start with something in the 4.7K range. Test your display with another micro, you may have open address select lines on the display.
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