Hi, I use CubeIDE to setup STM32G031F6P6 I2C2. I simply check the box for I2C2, see attached. In my circuit, I have pull ups on the I2C lines. However, when I try to send a I2C message, the SCL line shows no clock activity. The SDA line is always low.

[ltan.11]

I notice that the I2C1 setup in the IDE is different than the I2C2 setup. I will try I2C1 to see if it can work, but how would I get I2C2 working?

[Tesla DeLorean]

Well options there are that whatever else is attached to the bus is clamping them, or not in I2C mode (perhaps some SPI/I2C mode device), or that PA9/PA10 are in some initialized state (USART1) and conflicting with the settings on PA11/PA12

Check all your GPIO pin settings in code, and at register level.

Disconnect other portions of the circuit.

Check for shorts.

Perhaps check driving the GPIOs directly.