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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Transmission Position Sensor/Switch: Description and Operation

Park/Neutral Position Signal (A/T model only)
This signal is sent from transmission control module as a battery voltage signal only when A/T is in "R", "D", "2" or L" range. Thus, ECM judges whether A/T is in one of the above range or otherwise (i.e. in "P" or "N" range) and uses it as one of the signals to control the fuel injector, idle air control valve and ignition timing.