FORD 2012 F-150 Raptor v.1 - Manual (Page 273)

WIRING FAULT ON TRAILER: This message is displayed when a
Short circuit on the electric brake output wire has occurred. If the
WIRING FAULT ON TRAILER message is displayed and accompanied
by a single chime, with no trailer connected, the problem is with the
vehicle wiring from the TBC to the 7–pin connector at 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) or trailer brakes drawing
too much current.
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.
Points to Remember:
• Remember to adjust gain setting before using the TBC for the first
time.
• Readjust gain setting on the TBC (according to procedure above)
whenever road, weather and trailer or vehicle loading conditions
change from those that existed when the gain was initially set.
• The sliding lever on the TBC should be used only for manual
activation of trailer brakes to assist with proper adjustment of the
GAIN. Misuse, such as application during trailer sway, could cause
instability of trailer and/or tow vehicle.
• Avoid towing in adverse weather conditions. The TBC does not
provide anti-lock control of the trailer wheels. Trailer wheels can lock
up on slippery surfaces, resulting in reduced stability of trailer and
tow vehicle.
• The TBC is equipped with a feature which reduces output at vehicle
speeds below 11 mph (18 km/h) so trailer and vehicle braking is not
jerky or harsh. This feature is only available when applying the brakes
using the vehicle’s brake pedal, not the TBC.
• The TBC interacts with the brake system of the vehicle, including
ABS, in order to reduce the likelihood of trailer wheel lock-up;
therefore, if these systems are not functioning properly, the TBC may
not function at full performance.
• Your vehicle’s brake system and the trailer brake system work
independently of each other; changing the GAIN setting on the TBC
does not affect the operation of your vehicle’s brakes whether a trailer
is attached or not.
Tires, Wheels and Loading
273
2012 F-150 (f12)
Owners Guide, 1st Printing
USA (fus)