Normal Operation

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The Instrument Panel Cluster (IPC) receives the trunk ajar status from the Smart Junction Box (SJB) over the Medium Speed Controller Area Network (MS-CAN) communication bus. The luggage compartment lid ajar switch (part of the luggage compartment lid latch) is hardwired to the SJB through the trunk ajar input circuit. The luggage compartment lid ajar switch is grounded externally. When the luggage compartment lid is ajar, the luggage compartment lid latch removes the ground to the luggage compartment lid ajar switch input to the SJB . When the luggage compartment lid is closed, the luggage compartment lid release grounds the luggage compartment lid ajar switch.

When the SJB detects an open on the trunk ajar input circuit, the SJB sends a message to the IPC to turn on the TRUNK AJAR message in the message center.

This pinpoint test is intended to diagnose the following:

Wiring, terminals or connectors
Luggage compartment lid ajar switch (part of the luggage compartment lid latch)
SJB
IPC