Combination Switch Reading Function: Description

BCM reads the status of the combination switch at 10 ms interval normally.

Fig 1: Identifying Interval Between Consecutive BCM Combination Switch Reading
Courtesy of NISSAN NORTH AMERICA, INC.

NOTE: BCM reads the status of the combination switch at 60 ms interval when BCM is controlled at low power consumption mode.
BCM operates as follows and judges the status of the combination switch.
- INPUT 1 - 5 outputs the voltage waveforms of 5 systems simultaneously.
- It operates the transistor on OUTPUT side in the following order: OUTPUT 5 → 4 → 3 → 2 → 1.
- The voltage waveform of INPUT corresponding to the formed circuit changes according to the operation of the transistor on OUTPUT side if any (1 or more) switches are ON.
- It reads this change of the voltage as the status signal of the combination switch.
  
  Fig 2: BCM Input/Output Signal Operation Waveform
  Courtesy of NISSAN NORTH AMERICA, INC.