FORD 2013 Explorer v.4 - Manual (Page 117)

Charging system (RTT)
Illuminates when the battery is not charging properly. If it stays
on while the engine is running, there may be a malfunction with
the charging system. Contact your authorized dealer as soon as
possible. This indicates a problem with the electrical system or a related
component.
Door ajar (RTT)
Displays when the ignition is on and any door is not completely
closed.
Engine oil pressure (RTT)
Illuminates when the oil pressure falls below the normal range.
Engine coolant temperature (RTT)
Illuminates when the engine coolant temperature is high. Stop
the vehicle as soon as possible, switch off the engine and let
cool.
Fog lamps
Illuminates when the fog lamps are turned on.
Grade assist (if equipped) (RTT)
Illuminates when grade assist is turned on.
Heads up display (if equipped)
A red beam of lights will illuminate on the windshield in certain
instances when using adaptive cruise control and/or the
collision warning system. It will also illuminate momentarily
when you start your vehicle to make sure the display works.
116 Instrument Cluster
2013 Explorer (exp)
Owners Guide gf, 4th Printing, November 2012
USA (fus)