Ford F-150 Owner's Manual page 280

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 lock-up
may not be attainable even with the maximum gain setting of 10.
Explanation of Information Display Warning Messages
Note: An authorized dealer can diagnose the trailer brake controller to
determine exactly which trailer fault has occurred. However, your Ford
warranty does not cover this diagnosis if the fault is with the trailer.
TRAILER BRAKE MODULE FAULT: Displays in response to faults
sensed by the trailer brake controller, accompanied by a single chime.
If this message appears, contact an authorized dealer as soon as possible
for diagnosis and repair. The controller may still function, but
performance may be degraded.
WIRING FAULT ON TRAILER: Displays when there is a short circuit
on the electric brake output wire. If the WIRING FAULT ON TRAILER
message displays, accompanied by a single chime, with no trailer
connected, the problem is with your vehicle wiring between the trailer
brake controller and the 7–pin connector at the bumper. If the message
only displays with a trailer connected, the problem is with the trailer
wiring. Consult your trailer dealer for assistance. This can be a short to
ground (such as a chaffed wire), short to voltage (such as a pulled pin
on trailer emergency breakaway battery) or the trailer brakes may be
drawing too much current.
Points to Remember
Note: Do not attempt removal of the trailer brake controller without
consulting the Workshop Manual. Damage to the unit may result.
• Adjust gain setting before using the trailer brake controller for the
first time.
• Adjust gain setting, using the procedure above, whenever road,
weather and trailer or vehicle loading conditions change from when
the gain was initially set.
• Only use the manual control lever for proper adjustment of the gain
during trailer setup. Misuse, such as application during trailer sway,
could cause instability of trailer or tow vehicle.
• Avoid towing in adverse weather conditions. The trailer brake
controller 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.
2013 F-150 (f12)
Owners Guide gf, 3rd Printing, February 2013
USA (fus)
Towing 279