Pedestrian Protection Function - GF91.60-P-1005RF

Model 205, 253 

with code U60 (Active Bonnet (Pedestrian protection)) 

Function requirements, general 

• Terminal 15 ON
• Vehicle speed v = 25 to 55 km/h

The electronic ignition lock control unit (N73) sends the circuit 15 status over the user interface CAN (CAN HMI) to the supplemental restraint system control unit (N2/10).

The instrument cluster (A1) sends information about the vehicle speed via user interface CAN to the Supplemental Restraint System control unit.

Pedestrian protection, general 

The pedestrian protection reduces the level of injury severity in the event of any collision with a pedestrian. The space between the engine hood and the components below is increased by the engine hood moving up suddenly in the area of the A-pillar. This space prevents the pedestrian from being hit directly by the components below the engine hood.

Pedestrian protection includes the following subfunctions:

• Function sequence for impact detection 
• Function sequence for activating pedestrian protection 

Function sequence for impact detection 

The Supplemental Restraint System control unit reads in the signals directly from the following sensors:

• Left front bumper pedestrian protection sensor (B151/1)
• Right front bumper pedestrian protection sensor (B151/3)

The pedestrian protection sensors record the pressure in a hose located between the sensors. The pressure increases when the bumper is pressed in, for example. A decision is made about triggering the pedestrian protection depending on the determined pressure values.

The pedestrian protection may be actuated by mistake in a collision with other objects (e.g. pole, guide post or thick branches).

Function sequence for activating pedestrian protection 

The engine hood is lifted in the area of the A-pillar using the engine hood lifter. To do so, the Supplemental Restraint System control unit actuates the following squibs directly:

• Left active engine hood squib (R12/49)
• Right active engine hood squib (R12/50)

The status of the active engine hood squibs is monitored by the Supplemental Restraint System control unit. In case of error, a corresponding message is displayed on the multifunction display (A1p13) of the instrument cluster. The request for this is sent by the supplemental restraint system control unit over the user interface CAN to the instrument cluster.

Raising the engine hood has no further effects on the triggering behavior of the supplemental restraint system.

	Function schematic for electric pedestrian protection		PE91.60-P-2054-97FBA
	Overview of system components for supplemental restraint system		GF91.60-P-9996RF