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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Adaptive Memory Control


During closed loop operation, the ECU controls the duty cycle of the jet mixture control solenoid based on output voltage signals from the oxygen sensor. The mean (mid-point) values of the duty cycle are stored in the RAM (random access memory). The last signals received are stored, even when the ignition switch is turned Off.