This mechanism is called the Park/Neutral position switch, and this switch will not allow the engine to start in any other gear rather than Park and Neutral, and in case the engine starts in other gears, there needs adjustment in that switch. This same switch also gets used as the shift lock solenoid and acts as a sensor for ECT information for the ECM and sends a voltage signal when the shift lever is in the proper position. For verification of the switch, make it stand the front part of the vehicle on jackstands, disconnect the electrical connector and use an ohmmeter to measure the conductivity between the terminals indicted for each position of the switch; if the conductivity is not in the range as specified then replace the switch. For replacement, again raise the front of the vehicle, pull the electrical connector, removing the nut of the manual-lever, take out the manual lever, remove bolts and finally the switch. After that, the installation happens in the reverse order to check that the switch is well set. For adjustment, use a spanner to unscrew switch retaining bolts then turn the switch until the groove faces the neutral basic line then hold it to be tight by screwing the retaining bolts.