A trailer brake system is designed to receive electronic signals from your vehicle
and slow the trailer, but these could become interrupted if wires break or become corroded.
Although it may be possible to drive with the service trailer brake controller
message flashing in the DIC, doing so is not advised and you should seek immediate
solutions to resolve it as soon as possible.
Fuse
No matter if you are towing a trailer or boat, strong brakes are always beneficial. But
occasionally you may experience delays in braking processes, or feel as if there is
too little force when pressing on pedal. This problem could be caused by numerous
factors; even something as simple as loose connections in fuse boxes could contribute.
Fuse devices contain wire designed to melt at a specific temperature and are
installed into standard fuse sockets. If too much current passes through it, its
conductor can become overheated to its melting point and break the circuit by
reaching overheat levels that exceed its melting point and break off its connection
with other circuit elements.
GM trailer brakes feature an advanced monitoring system designed to track vehicle
and trailer components. This should generate codes that help identify issues with
controller or wiring issues; however, some dealerships have reported that such
codes are no longer being generated.
Brake Pads
Brake pads are one of the most crucial elements in a trailer’s braking system, so
regular replacement should be scheduled to ensure their effectiveness and avoid
potential accidents caused by premature wearout of pads. If this step is neglected,
they could wear out earlier and lead to potentially life-threatening accidents.
If the “Service Trailer Brake System” warning light illuminates on your GM truck
dashboard, it’s time to replace your brake pads. This dashboard indicator light may
signal several different problems including low brake fluid levels or an ineffective
parking brake mechanism; additionally it could point out any possible malfunction
with electro-over hydraulic pump motor.
Modern trailer brakes are generally electric systems. These brakes use a powerful
magnetic field to stop the wheels of a trailer and are controlled by a brake control
unit in the towing vehicle. This type of system can often be found on boat trailers,
travel trailers and enclosed trailers and is especially susceptible to corrosion, binding
and wire deterioration issues that negatively impact its effectiveness.
Brake Lights
Most trailers feature brake lights that activate whenever someone presses down on
the brake pedal, but if yours aren’t functioning it could be because their wiring has
become disconnected – or maybe this indicates your brake pads have worn down!
Fuse problems are usually at the heart of service trailer brake system messages, as
these powering components of your truck’s electronics depend on receiving enough
electricity to function properly. A blown fuse should be easy to identify and replace
so you can continue driving safely.
Starting by unhooking the lock nut using a screw driver and unthreading its screw,
twist the adjusting nut clockwise to reset it if it looks rusty or dirty. Reattach all parts
back together using their original locations; this should address your service trailer brake system warning.
Wiring
A trailer braking system requires constant contact between itself and a truck in
order to provide power and signals. This is accomplished using a fuse and wiring
diagram specific for this system. These circuits are constantly monitored by the cab
control module (CCM) in order to ensure they contain sufficient voltage levels and all
required circuits are connected; should one not connect, or interrupt, CCM will send
a test pulse onto circuit 47 of trailer solid state relay, as well as show an “Check
Trailer Wiring” or “Service Trailer Brake System” message on DIC display screen.
Fuses in this system can often blow, so be sure to double-check all fuses at your
power distribution center or under the hood, including Park lamp fuse INT PRK 10
amp in your instrument panel fuse box and use a voltmeter when checking them; in
addition, spraying some WD-40 on 7-way connector pins may help with connections