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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Inhibitor Switch (A/T)

Inhibitor Switch:






The Inhibitor Switch (also referred to as neutral safety switch) signals the ECU as to transmission operating range and prevents starting the vehicle except in "P" or "N" positions.

The ECU utilizes the transmission operating range input from the inhibitor switch in its control calculations for these outputs:

^ Fuel injection quantity
^ Pressure regulator solenoid valve
^ Idle speed control
^ Purge solenoid valve
^ A/C cut-off