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

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Catalytic Converter Protection Function (Ign. Cir. Monitoring)

OPERATION
Malfunctions on the primary side of the ignition system are detected by the Digital Motor Electronic (DME) control unit and result in the injector valve on the relevant cylinder being switched off. This prevents an impermissible accumulation of uncombusted gasses in the catalytic converter.