Next step is to erase them and see if they come back. Hold down the button for 8-10 seconds to erase each one. It's important not to abbreviate too much, e.g. code 19 is more likely "system adaptation at limit" - try a search for code 19 and JimF's chip to resolve. Code 6 is telling you to read the faults on pin 7. Code 20 is saying your speedo is/was broken or disconnected. But first erase, drive the car and worry only about the codess that come back.