SRS-ECU



In addition to the analogue G-sensor and safing G-sensor for the frontal collision, the SRS-ECU incorporates the analogue G-sensor and safing G-sensor for the side collision. Upon a frontal collision, when the impact G is simultaneously detected by the front impact sensor in the engine room, analogue G-sensor, and safing G-sensor for the frontal collision in SRS-ECU, SRS-ECU outputs the ignition signal to the driver’s and passenger’s (front) air bag modules (squibs).
Upon a side collision, when the lateral impact G is simultaneously detected by the analogue G-sensor of side impact sensor and the safing G-sensor for side collision in SRS-ECU, the SRS-ECU outputs the ignition signal to the side-airbag module (squib) and the curtain air bag module (squib) of the relevant side that is subjected to the impact.
Also, SRS-ECU has the following functions that improve the system reliability.



DIAGNOSIS FUNCTION


To improve the system reliability, SRS-ECU performs the diagnostics of each part. If a malfunction is detected, it lights up the SRS warning lamp, and stores the contents as the corresponding diagnosis code. Also, to facilitate the system check, it has the following functions, and the check can be performed using M.U.T.-III.


DIAGNOSIS CODE SET


SRS-ECU performs a self-diagnosis on the following items. If a malfunction is detected, its content (diagnosis code) is stored in the involatile memory (EEPROM*). Therefore, the diagnosis code will not be erased even when the battery terminal is disconnected. The diagnosis code can be erased using M.U.T.-III.
note
  • *: EEPROM (Electrical Erasable & Programmable Read Only Memory): ROM that can be programmed or erased electrically
  • For each diagnosis item, refer to Workshop Manual.

DATA LIST OUTPUT


Using M.U.T.-III, the service data can be read.
note For service data items, refer to Workshop Manual.

ACTUATOR TEST


Using M.U.T.-III, the actuator can be forcibly operated. For the actuator test specification, refer to Workshop Manual.