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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Emission Control Systems: Testing and Inspection

To avoid potential misdiagnosis and the unnecessary replacement of components, it is recommended that diagnosis and testing begin with Diagnostic Routines (Diagnosis by Symptom) at the Powertrain Management level.
The Diagnostic Routines will lead the technician through the logical and methodical testing of a "specific" subsystem and it's related wiring and components.