MacBook Air (3209-A): Not charging, no speaker, no USB, + kernel panic

My MacBook Air is having some serious and very annoying issues.

The computer receives power from the charger, but the charger light does not come on, nor does the battery charge.

The internal speakers are not recognized. They do not show up in the preferences and the volume cannot be adjusted.

Also the (left) USB port on the same side as the charger does not work. The USB port on the other side is fully functional.

When booting the device it takes around 10-15 minutes to complete. When finally booted the device is extremely slow and the fans spin at 100%. The Activity Monitor shows met that "kernel_task" takes up to 400% of the CPU usage.

Things I have done to try and solve this are:

- SMC Reset

- PRAM Reset

- Apple Hardware Test (not booting, error -2002D)

- Check all cables on the I/O and logic board

The MacBook was NOT exposed to any form of liquid damage.

I do have experience in fixing laptops in the past so replacing or measuring parts won't be the problem. Will replacing the I/O board solve my problems?