Chart #1 Scan Tool Will Not Communicate With Class 1

Chart #1 Scan Tool Will Not Communicate With The Class 1 Serial Data Line (Part 1 Of 2):

Chart #1 Scan Tool Will Not Communicate With The Class 1 Serial Data Line (Part 2 Of 2):

Chart #2 Scan Tool Will Not Communicate With The Class 2 Serial Data Line (Part 1 Of 2):

Chart #2 Scan Tool Will Not Communicate With The Class 2 Serial Data Line (Part 2 Of 2):