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)

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Generic Electronic Module (Gem)

NOTE: Upon installation of a new Generic Electronic Module (GEM), the module must be reconfigured. Refer to Module Communications Network (Information Bus).

The GEM constantly monitors its subsystems for concerns. If a concern is found in one of the subsystems, the GEM will record the concern in the form of a Diagnostic Trouble Code (DTC). The ignition switch position is very important to the GEM function. Often times, erratic or unexpected GEM function can be traced to problems with ignition switch inputs.