FORD 2012 F-550 v.3 - Manual (Page 15)

Standard message center
Note: Some warning lights are
reconfigurable telltale (RTT)
indicator lights and will illuminate in
the message center. These lights
function the same as the other
warning lights.
Optional message center
Note: Some warning lights are
reconfigurable telltale (RTT)
indicator lights and will illuminate in
the message center. These lights
function the same as the other
warning lights. The first three
positions will only display one
warning telltale at a time; the last
three positions can cycle between
different warning telltales.
Service engine soon: The service
engine soon indicator
illuminates when the ignition is first
turned to the on position to check
the bulb and to indicate whether the vehicle is ready for
Inspection/Maintenance (I/M) testing. Normally, the service engine soon
indicator will stay on until the engine is cranked, then turn itself off if no
malfunctions are present. However, if after 15 seconds the service engine
soon indicator blinks eight times, it means that the vehicle is not ready
for I/M testing. See the Readiness for Inspection/Maintenance (I/M)
testing in the Maintenance and Specifications chapter.
Solid illumination after the engine is started indicates the on-board
diagnostics system (OBD-II) has detected a malfunction. Refer to
On-board diagnostics (OBD-II) in the Maintenance and Specifications
chapter. If the light is blinking, engine misfire is occurring which could
damage your catalytic converter. Drive in a moderate fashion (avoid
heavy acceleration and deceleration) and have your vehicle serviced
immediately by your authorized dealer.
Instrument Cluster
15
2012 F-250/350/450/550 (f23)
Owners Guide, 3rd Printing
USA (fus)