Normal Operation
WARNING: This page is about a different car, the 2008 Mercury Sable, 2008 Ford Taurus X, and 2008 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
The Battery Junction Box (BJB) receives battery voltage along circuit SDC02 (RD) and distributes this voltage to various fuses. The ignition switch receives fused battery voltage from BJB fuse 33 (20A) along circuit SBB33 (RD). The ignition switch then sends that voltage out to various systems depending on ignition switch position. The ignition switch has 4 possible states:
- OFF - Power on circuit CDC30 (BU/GY) to the Smart Junction Box (SJB)
- ACC - Power on circuit CDC33 (VT/GN) to the SJB
- RUN - Power on circuit CDC34 (WH/OG) to the SJB and BJB
- START - Power on circuit CDC35 (BU/WH) to the BJB and PCM
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Ignition switch
- BJB