2011 Mustang V6 Manual - 135,000 miles (daughter's first car). With trunk closed, when driving down the road the "trunk ajar" light appears on the dash and randomly dings. I can't get this to stop and I am losing my mind. Sometimes the trunk will pop open by switch on console, sometimes the key fob works, other times it doesn't. I checked the fuse, replaced the motor in the trunk lid with ford OEM part, and reset the gauge cluster and adjusted the bump stops, ensured the alignment was accurate, but I still have the problem. The warning continues to randomly appear and sometimes the trunk will release when requested. Crawling through the back seat to tug on the emergency release absolutely sucks.
The same circuit as the door locks control the trunk release. No problems with door lock/unlock (inside car and key fob). The local dealer wants to charge me to think about the problem, not to mention putting their hands on the car...Geez.
Any suggestions?
Mustang Head Hurts
An intermittently bad Ground could be causing your problem.
When the luggage compartment latch is closed the luggage compartment latch switch is also closed (position 1 in the diagram) and it provides a Ground to the Trunk Ajar Light circuit from Ground Point G402 and the Trunk Ajar Light isn't illuminated.
When the luggage compartment latch is open the luggage compartment latch switch is also open (position 2 in the diagram) the Trunk Ajar Light circuit loses the Ground from Ground Point G402 and illuminates the Trunk Ajar Light.
Also, the Luggage Compartment Latch Solenoid uses that same Ground Point in its circuit so it can't work without it.
The diagram shows that Ground wire is the Black and White wire on the 4 wire connector on the Luggage Compartment Latch Solenoid. Check the wiring connector at the Solenoid for a loose/damaged wire or corroded pin socket. Check the G402 Body Ground Point. Check the condition of the Black and White wire between those two
