CONSTRUCTION
The pedestrian detection ECU assembly consists of judgment circuits, an ignition control circuit, a backup power circuit, a diagnostic circuit and a memory circuit.
| Item | Outline |
|---|---|
| Judgment Circuit | Judgment circuits are built into the pedestrian detection ECU assembly to judge the severity of a collision using the pressure signal from the pedestrian protection sensors. |
| Ignition Control Circuit | The ignition control circuit performs calculations based on the signal output from the judgment circuit of the pedestrian detection ECU assembly and pedestrian protection sensors. If the calculated values are greater than the specified values, the pop up hood lifters are deployed. |
| Backup Power Circuit | The backup power circuit consists of a power supply capacitor and a DC-DC converter. When the power supply to the pedestrian detection ECU assembly is disrupted during a collision, the power supply capacitor discharges and supplies electric power to the system. The DC-DC converter operates as a boosting transformer when the battery voltage falls below a predetermined level. |
| Diagnostic Circuit | The diagnostic circuit constantly monitors the system for malfunctions. When a malfunction is detected, it turns on the master warning light in the combination meter assembly to inform the driver. |
| Memory Circuit | When a malfunction is detected by the diagnostic circuit, a DTC is stored in memory. |