Operation CHARM: Car repair manuals for everyone.
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

Class 2 Serial Data Link

The class 2 serial data link allows the following modules to communicate and share data with each other:
^ Powertrain Control Module (PCM)
^ Inflatable restraint Sensing And Diagnostic Module (SDM)
^ Electronic Brake Control Module (EBCM)
^ Instrument Cluster (IPC)
^ Heater-A/C Control (W/CJ2)
^ Body Control Module (BCM) Radio
^ OnStar

The class 2 serial data link allows a scan tool to communicate with the above modules for diagnostic and testing purposes.

For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the RPO Code List found at Vehicle/Application RPO Codes