GMC Sierras equipped with factory integrated trailer brake control (ITBC) may
display the message “Service Trailer Brake System” on their driver information
center (DIC), due to various reasons including an improperly functioning ITBC or
wiring problems. This error message may display in response to various events
including malfunctioning components within ITBC system or wiring issues that need attention.
Driving with this message displayed may be possible, but is neither safe nor
recommended. To resolve the problem effectively and safely, resetting the ITBC
system may help.
1. Check the Fuse
If the Service Trailer Bra System Warning Message displays on your monitor, this
indicates there is an issue with power supply to the trailer braking controller. This
could be caused by a broken brake light switch or fuse blowing out. In order to
address this problem effectively and promptly, you should first inspect all fuses in
your power distribution center – and replace any that are found to have blown.
If your trailer braking controller is malfunctioning, replacing it may also be costly;
however, its replacement should ensure safe driving for both yourself and others.
Repair costs typically hover around $300; this figure may differ depending on its
type or the auto technician who performs repairs; be sure to budget for this expense
when planning on buying a truck.
2. Check the Wiring
Your car relies on fuses to monitor power. When too much voltage passes through
the system, a fuse can blow, signalling that there may be an underlying issue that
needs addressing. If replacing a fuse does not resolve it, seek professional assistance immediately.
Fuse for trailer brake controller is usually located within your power distribution
center, which may be found either underneath the hood or on the dashboard of your
vehicle. A screwdriver and some time of your time is all you will need to locate and replace this fuse.
Check your wiring by taking another approach – by removing and adjusting its
wheel. A star wheel adjuster or flathead screwdriver should be used to turn its
adjustment nut clockwise until you cannot turn the wheel easily or quickly, then
loosen it until rotation can resume easily and rapidly.
3. Check the Brake Lights
Your trailer’s braking system must be functioning flawlessly to effectively stop when
you apply the brakes, without compromising control or leading to accidents or
damages. Therefore, it is recommended that you regularly inspect and fix any
potential problems in this regard.
If your dashboard displays the message “Service Trailer Bra System,” this indicates
that your ITBC-integrated trailer brake controller has some sort of wiring issue or
something is blocking electricity from moving from the truck to your trailer
connection. Before driving your truck with its trailer attached, this must be corrected
before driving with one attached.
Simple fixes to your ITBC can help to eliminate the service trailer brake system
warning on your GMC Sierra, such as unplugging it or cutting its output wire completely.
4. Check the Brakes
Your trailer brake controller sends signals to your truck and trailer’s brakes, but if a
wire gets cut or frayed it could prevent your system from receiving accurate
information and trigger an alert light on your dashboard. In such instances, it would
be wise to contact an expert to assess all wiring connections to ensure they’re all operating as planned.
Every electronic component in your vehicle relies on fuses to monitor power, so as
to detect when too much voltage passes through a circuit and blow fuses are an
indicator of larger problems that need to be addressed immediately. When one
blows, there may be additional concerns that require immediate attention.
Unplug your brake controller to prevent electricity or power from reaching the
brakes, or cut any wire between it and them if your controller is hardwired to your
trailer.