Normal Operation
WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
The ignition switch receives fused battery voltage along circuit SBP27 (BU/RD) from smart junction box (SJB) fuse 27 (20A). The ignition switch then sends that voltage out to various systems depending on ignition switch position. The SJB continuously monitors the ignition switch state.
- DTC B2844 Ignition Fault - If the SJB receives an invalid ignition state or cannot receive the ignition switch state during normal operation, DTC B2844 is set.
- DTC U2472 Unexpected Ignition State - If the SJB does not receive the ignition RUN signal, or any ignition switch signal, while performing an on-demand self test, DTC U2472 is set.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Ignition switch
- SJB