GM YUKON XL Automobile User Manual


 
Manual Trailer Brake Apply
The Manual Trailer Brake Apply Lever is located on the
Trailer Brake Control Panel and is used to apply the
trailer s electric brakes independent of the vehicles
brakes. This lever is used in the Trailer Gain Adjustment
Procedure to properly adjust the power output to the
trailer brakes. Sliding the lever to the left will apply only
the trailer brakes. The power output to the trailer is
indicated in the Trailer Brake Display Page in the DIC.
If the vehicles service brakes are applied while using
the Manual Trailer Brake Apply Lever, the trailer output
power will be the greater of the two.
The trailer and the vehicle's brake lamps will come on
when either vehicle braking or manual trailer brakes are
applied.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific trailering
condition and must be adjusted any time vehicle
loading, trailer loading or road surface conditions
change.
Setting the Trailer Gain properly is needed for the
best trailer stopping performance. A trailer that is
over-gained may result in locked trailer brakes. A trailer
that is under-gained may result in not enough trailer
braking. Both of these conditions may result in poorer
stopping and stability of the vehicle and trailer.
Use the following procedure to correctly adjust Trailer
Gain for each towing condition:
1. Make sure the trailer brakes are in proper working
condition.
2. Connect a properly loaded trailer to the vehicle
and make all necessary mechanical and electrical
connections. See Loading the Vehicle
on
page 531
for more information.
3. After the electrical connection is made to a trailer
equipped with electric brakes:
.
A TRAILER CONNECTED message will be
briefly displayed on the DIC display.
.
The Trailer Brake Display Page will appear
on the DIC showing TRAILER GAIN and
TRAILER OUTPUT.
.
In the Trailer Output display on the DIC,
- - - - - - will disappear if there is no error
present. Connecting a trailer without electric
brakes will not clear the six dashed lines.
4. Adjust the Trailer Gain by using the gain
adjustment (+ / -) buttons on the Trailer Brake
Control Panel.
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