Tires, wheels and loading – FORD 2012 F-550 v.3 User Manual
Page 260
activated while the brake is also applied, the greater of the two inputs
determines the power sent to the trailer brakes.
• Stop lamps: Activating the TBC manual control lever illuminates both
the trailer brake lamps and the tow vehicle brake lamps except the
center high-mount stop lamp (presuming proper trailer electrical
connection). Pressing the vehicle brake pedal also illuminates both
trailer and vehicle brake lamps.
Procedure for adjusting GAIN:
The GAIN setting is used to set the TBC for the specific towing
condition and should be changed as towing conditions change. Changes
to towing conditions include trailer load, vehicle load, road conditions
and weather.
The GAIN should be set to provide the maximum trailer braking
assistance while ensuring the trailer wheels do not lock when braking;
locked trailer wheels may lead to trailer instability.
Note: This should only be performed in a traffic-free environment at
speeds of approximately 20–25 mph (30–40 km/h).
1. Make sure the trailer brakes are in good working condition,
functioning normally and properly adjusted. See your trailer dealer if
necessary.
2. Hook up the trailer and make the electrical connections according to
the trailer manufacturer’s instructions.
3. When a trailer with electric brakes is plugged in, the TRAILER
CONNECTED message displays in the instrument cluster message
center.
4. Use the GAIN adjustment (+/-) buttons to increase or decrease the
GAIN setting to the desired starting point. A GAIN setting of 6.0 is a
good starting point for heavier loads.
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 lock-up
may not be attainable even with the maximum GAIN setting of 10.
Tires, Wheels and Loading
260
2012 F-250/350/450/550 (f23)
Owners Guide, 3rd Printing
USA (fus)