Description & Operation

WARNING: Vehicle is equipped with Supplemental Inflatable Restraint (SIR) system. When servicing vehicle, use care to avoid accidental air bag deployment. SIR system-related components are located in various locations throughout interior and exterior of vehicle, depending on application. Do not use electrical test equipment on or near these circuits. If necessary, deactivate SIR system before servicing components. See appropriate AIR BAG DEACTIVATION PROCEDURES article in GENERAL INFORMATION.

The shift interlock system consists of an electro-magnetic solenoid mounted on upper steering column. See Fig 1 . Brake Transmission Shift Interlock (BTSI) solenoid is controlled by the Front Control Module (FCM). The FCM is connected to underhood fuse and relay center creating the Intelligent Power Module (IPM). IPM is located in left front corner of engine compartment. See Fig 2 . With ignition switch in LOCK or ACC position, the gearshift lever is locked in Park. Depressing brake pedal with ignition switch in ON/RUN or START positions de-energizes BTSI solenoid. Solenoid plunger disengages shift lever pawl and allows gearshift lever to be moved to any position. See Fig 3 .

A conventional mechanical interlock system is also used. System manually prohibits gearshift lever movement when ignition switch is in LOCK or ACC positions. Solenoid does not function in these positions. Gearshift lever can be moved with ignition switch in OFF position. This enables vehicle to moved in the event the battery is dead or removed. Shift interlock system prevents ignition switch from being rotated to LOCK or ACC position unless gearshift lever is returned to Park.

Fig 1: Locating Brake Transmission Shift Interlock Solenoid

Courtesy of DAIMLERCHRYSLER CORP.

Fig 2: Locating Front Control Module & Intelligent Power Module

Courtesy of DAIMLERCHRYSLER CORP.

Fig 3: BTSI Pawl Disengaged From Shift Lever

Courtesy of DAIMLERCHRYSLER CORP.