Manuals through 2025 now available!
Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.
LEMON is the spiritual successor to CHARM, I recommend you try it!
Link:
lemon-manuals.la or
lemon-manuals.org.ua
(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)
Or, hide this message:
temporarily or
permanently
Preliminary Information
Regulations require that all automobile manufacturers establish a common communications system. The communication between the
powertrain control module and the off-board diagnostic equipment (scan tool) is achieved on a serial communication line. Serial data is sent in linear form, one bit at a time, over the communication line.