FORD 2007 F-550 v.1 - Manual (Page 163)

5. In a traffic-free environment, tow the trailer on a dry, level surface at
a speed of 20 – 25 mph (30 – 40 km/h) and squeeze the manual control
lever completely.
6. If the trailer wheels lock-up (indicated by squealing tires), reduce the
GAIN setting; if the trailer wheels turn freely, increase the GAIN setting.
Repeat Steps 5 and 6 until the GAIN setting is at a point just below
trailer wheel lock-up. If towing a heavier trailer, trailer wheel lockup may
not be attainable even with the maximum GAIN setting of 10.
Explanation of instrument cluster messages:
The TBC interacts with the instrument cluster message center. These
messages, accompanied by a single chime, will be displayed when the
TBC determines a malfunction in the trailer connection, TBC system, or
in the trailer. These messages are listed below:
TRAILER DISCONNECTED (if equipped with message center) or
CHECK TRAILER (if equipped with mini message center): This
message is displayed when a trailer connection was determined and then
a disconnection, either intentionally or unintentionally, has been sensed
during a given ignition cycle. It is also displayed if a trailer fault occurs
causing the trailer to appear disconnected. This message is also
displayed during manual activation without a trailer connected.
TBC FAULT: This message is displayed in response to faults sensed by
the TBC. In the event this message is seen, please take your vehicle to
an authorized dealer for diagnosis and repair. The TBC may still function,
but performance may be degraded.
TRAILER FAULT: The TBC is capable of determining certain faults in
the vehicle wiring and trailer wiring/brake system. These faults do not
mean there is anything wrong with the TBC. This message is displayed
when one of the following faults has occurred:
• Short circuit on the electric brake output wire: If the TRAILER
FAULT message is displayed with no trailer connected, the problem is
with the vehicle wiring from the TBC to the 7–pin connector in the
bumper. If the message is only displayed with a trailer connected, the
problem is related to the trailer wiring; consult your trailer dealer for
assistance. This can be a short to ground (i.e., chaffed wire) or a short
to voltage (i.e., pulled pin on trailer emergency break-away battery).
• Trailer brake overload: The trailer brakes are drawing too much
current; consult your trailer dealer for assistance.
Note: Your TBC can be diagnosed by your authorized dealer to determine
exactly which trailer fault has occurred; however, if the fault is with the
trailer this diagnosis is not covered under your Ford warranty.
2007 F-250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA (fus)
Tires, Wheels and Loading
163