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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Engine and Emission Control System

Fail-safe function
Even when a trouble has occurred in such area of engine & emission control system that includes the parts described in fail-safe table and a failure signal is sent to ECM (PCM), control over the injections, IAC valve and others is maintained on the basis of the standard signals and/or back-up program prestored in the ECM (PCM) while ignoring that failure signal and/or CPU. This function is called "fail-safe function". Thus, with this function, a certain level of engine performance is available even when some failure occurs in such area and disability in running is avoided.