I would say you either have a 5v supply fault with the 3 sensors/components (wire fault or ecu) or a missing switched earth which is ecu conrolled.

Check to see if the earth wire on the ecu casing is tight and clean or even if its fitted, if not make your own from the battery - to the casing.

Ecu pin A9 is the earth circuit for the MAF.CTS and EGR valve.

Pin 3 (brown wire) at MAF meter is ecu earth.

The other 2 codes i'm not sure about but could also be caused by eath issues.