Operation CHARM: Car repair manuals for everyone.

CNG

When ignition switch is turned to the OFF position, the Powertrain Control Module (PCM) stops operating the fuel injectors, ignition coil, automatic shut-down (ASD) relay and CNG high-pressure fuel shut-off solenoid relay.

Fuel flow is electrically stopped (shut-down) at both the tow-pressure and high-pressure fuel shut-off solenoids.