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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Diagnostic Messages

Diagnostic Chart:




Wiring Diagram:






1. This test determines if the Class 2 Data Bus itself is malfunctioning.

2. This test checks for a short to ground in CKT 1807.

3. This test checks for a short to voltage in CKT 1807.

4. This test starts a process to determine which module is causing the Class 2 Data Bus to stop communicating.