OSS-related malfunction warning tone alarm (vehicles with OSS)

WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.

Ignition switch signal
When the following conditions are met, and 1 second or more has elapsed.
1. +B1 is detected to be ON and +B2 is detected to be OFF.
2. When +B1 is OFF and +B2 is ON, OSS-ECU detects that the IOD fuse is mounted.