GMC Hummer EV 2024 Owner's Manual page 271

GMC Hummer EV Owner Manual (GMNA-Localizing-MidEast-16639039) -
2024 - CRC - 3/20/23
the output to the trailer off, adjust the
Trailer Gain setting to 0.0. This setting can
be adjusted from 0.0 to 10.0 with a trailer
connected or disconnected.
TRAILER OUTPUT: This displays anytime a
trailer with electric brakes is connected.
Output to the trailer brakes is based on the
amount of vehicle braking present and
relative to the Trailer Gain setting. Output is
displayed from 0 to 100% for each gain
setting.
The Trailer Output will indicate - - - - - - on
the Trailer Brake Display Page whenever the
following occur:
No trailer is connected
A trailer without electric brakes is
connected, no DIC message will display
A trailer with electric brakes has become
disconnected, a CHECK TRAILER WIRING
message displays on the DIC
There is a fault present in the wiring to
the trailer brakes, a CHECK TRAILER
WIRING message displays on the DIC
The ITBC system is not working due to a
fault, a SERVICE TRAILER BRAKE SYSTEM
message displays in the DIC
Manual Trailer Brake Apply Lever
Slide this lever right to apply the trailer
electric brakes independent of the vehicle
brakes. Use this lever to adjust Trailer Gain
to achieve the proper power output to the
trailer brakes. This lever may also be used
to request additional trailer braking at any
time. The trailer and vehicle brake lamps
will come on when either vehicle brakes or
manual trailer brakes are applied and
properly connected.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific
trailering condition and it must be
readjusted anytime vehicle loading, trailer
loading, or road surface conditions change.
Warning
Trailer brakes that are over-gained or
under-gained may not stop the vehicle
and the trailer as intended and can result
in a crash. Always follow the instructions
to set the Trailer Gain for the proper
trailer stopping performance.
To adjust Trailer Gain for each towing
condition:
Driving and Operating
1. Drive the vehicle with the trailer
attached on a level road surface
representative of the towing condition
and free of traffic at about 32 to
40 km/h (20 to 25 mph) and fully apply
the Manual Trailer Brake apply lever.
Adjusting Trailer Gain at speeds lower
than 32 to 40 km/h (20 to 25 mph) may
result in an incorrect gain setting.
2. Adjust the Trailer Gain, using the Trailer
Gain adjustment buttons, to just below
the point of trailer wheel lockup,
indicated by trailer wheel squeal or tire
smoke when a trailer wheel locks. Trailer
wheel lockup may not occur if towing a
heavily loaded trailer. In this case, adjust
the Trailer Gain to the highest allowable
setting for the towing condition.
3. Readjust Trailer Gain any time vehicle
loading, trailer loading, or road surface
conditions change or if trailer wheel
lockup is noticed at any time while
towing.
Other ITBC-Related DIC Messages
TRAILER BRAKES CONNECTED: This message
will briefly display when a trailer with
electric brakes is first connected to the
vehicle. This message will automatically turn
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