A while back TJ posted a message on getting test codes out of the OBC by pressing the 1000 and 10 together, then entering 19 and typing the sum of the date numbers and then pressing the S/R button. Once you unlock this system you can then update or check various items. Does anyone have any additional details on how to read some of the test codes. I'm specifically interested in the ones for the Production Diagnosis, tests 15 and 16.