Combination Switch Reading Function: Description

WARNING: This page is about a different car, the 2011 Nissan Xterra. However, it is still accessible from the selected car via links, so may be relevant.

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

Fig 1: BCM Timing Chart

NOTE: BCM reads the status of the combination switch at 20 ms interval when BCM is controlled at low power consumption control 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: Input/Output Signal Operation Chart