Hi. I have a e60 530d 2006/03 with passive go system. The easy entry only works sporadic. I think that the car key is broken.
My question is if i buy a used key from another car with pgs can autohex program it to the car?

You can teach a used key only if you have the data of this key.
To get data file using Autohex II, you have to connect Autohex II to the CAS which has this key and go to key learning->button 1. Then select the key you want to save it's data, then click on Save.
After you save this data you can use the key in any other car.
Please see details in this link:
http://www.micro-tronik....s3+/manage-current-keys/ 

Can i read or it's ok if i read key data with avdi key tag or hitag?

The key is locked, you cannot read it by any tool.
If you can read data ( I am sure you cannot), then you can use these data in Autohex II. key learning button 3
See this link:
http://www.micro-tronik....3+/program-prepared-key/