Pedestrian Protection System - Description

PEDESTRIAN PROTECTION SYSTEM

An Electronic Pedestrian Protection (EPP) system (also known as the PedPro or the Active Hood System) is factory-installed safety equipment, which is available only in vehicles manufactured for certain export markets. The EPP system includes the following major components, which are described in further detail elsewhere in this service information:

- Active Hood Hinge Actuators - The two pyrotechnic EPP active hood hinge actuators are each secured by a screw within a mounting plate located on each of the two active hood hinges, which are located near each rear corner of the hood panel.

- Active Hood Hinges - The active hood hinges have several features and components not found on a conventional hood hinge. In addition to a mounting plate for a pyrotechnic actuator and a reset spring, each active hood hinge includes a mid-strap joined to the hood bracket by a pivot pin at the forward end and a shear rivet at the rearward end. An up-stop pin near the center of the hood bracket fits within a slotted hole near the center of the mid-strap. Refer to Body and Frame for hood hinge removal and installation procedures.

- Electronic Pedestrian Protection Module - The Electronic Pedestrian Protection Module (EPPM) is located on a stamped metal mounting bracket welded onto the cross-car instrument panel support beam outboard of the steering column. The EPPM is secured to three studs on the mounting bracket by three hex nuts.

- Front Energy Absorber Foam Material - The front energy absorber foam material is sandwiched between the front bumper area of the front fascia and the front bumper support beam. Refer to Body and Frame for front fascia removal and installation procedures.

- Impact Sensors - The EPP system includes three dedicated acceleration-type impact sensors to support the EPP feature. The impact sensors are each mounted by a hex nut to a weld stud within a dedicated bracket located on the top surface of the front bumper support beam. One sensor and bracket is located near each end of the bumper support beam, and one is located near the center. The impact sensors and brackets are concealed behind the front fascia.

- Pedestrian Bar - A static, tubular metal pedestrian bar (also known as a leg catcher) is concealed just behind the lower end of the front fascia. The pedestrian bar is suspended at each side from the lower end of a stamped metal bracket that is secured at the top near the same brackets that support each end of the front bumper support beam. Refer to Body and Frame and Bumpers for the pedestrian bar removal and installation procedures.

The EPPM and the Occupant Restraint Controller (ORC) each contain a microcontroller and include programming that allow them to communicate with each other using the Controller Area Network (CAN) data bus. This method of communication is also used by the ORC for control of the airbag indicator in the Instrument Cluster (IC) (also known as the Common Instrument Cluster/CIC). Communication - Description.

Hard wired circuitry connects the EPP electronic components to each other through the electrical system of the vehicle. These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system, and to the EPP components through the use of a combination of soldered splices, splice block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, further details on wire harness routing and retention as well as pin out and location views for the various wire harness connectors, splices and grounds.