•Stop Lamps:Activating the TBC manual control lever will illuminate
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 will also illuminate both
trailer and vehicle brake lamps.
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.
Procedure for adjusting GAIN:
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 connection
indicator will illuminate green on the TBC and the GAIN setting display
will illuminate.
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 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
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
225
