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

Operation






OPERATION

The microprocessor-based DDM and PDM hardware and software monitors integral and hard wired external switch inputs as well as those resources it shares with other electronic modules in the vehicle through its communication over the CAN data bus network. The internal programming and all of these inputs allow the DDM or PDM microprocessor to determine the tasks it needs to perform and their priorities, as well as both the standard and optional features that it should provide.