The trailer brake system is intended to enable smooth travel with loads attached,
yet is susceptible to issues such as wire deterioration, binding, and corrosion.
Maintain a culture of 100% safety awareness to avoid issues with trailer brakes.
Should the “Service Trailer Brake System” message appear, there are steps that you
can take to remedy the situation.
Brake Shoes
Brake shoes and pads are designed to wear down over time. That is because both
contain a sacrificial friction material which wears away so as to maintain functional
components without disruption or degradation.
Both brake shoes and pads are constructed from metal plates – with shoes being
curved while pads being flat – attached to which is adhered a special friction
material, each type offering its own distinct advantages and disadvantages.
Brake shoe sets typically include springs, pins and adjusters to assist with their
operation and mounting. Over time these parts may wear out; to maintain optimal
performance of the entire system, replacing all hardware at the same time as the
shoes should ensure optimal operation of each component of the system.
Brake Pads
When servicing trailer brakes, the first thing to consider is their condition of brake
pads. If they appear worn-out or frayed, replacing them as soon as possible before
they cause irreparable damage is essential.
Use the ITBC control panel to adjust Trailer Gain power available to trailer brakes.
Furthermore, manually apply them using the lever located on DIC.
When an electrical problem arises with your electric trailer brake system, the
“CHECK TRAILER WIRING” message may appear on your DIC. As this is a safety
concern, if this message keeps appearing repeatedly it indicates an electrical fault
which must be addressed by an expert technician immediately.
Brake Cables
The brake cable connects the trailer controller with the braking components, playing an essential role in how well they function as part of an effective system. It connects to both a brake lever and controller and sends out signals that activate trailer brakes – saving wear and-tear on vehicle brakes while helping avoid excessive wear-and-tear.
To address this problem, pouring a can of WD-40 over the wiring connection will
quickly eliminate all dust and other foreign elements that have built up over time.
Furthermore, it will strengthen connector pin connections – commonly located inside
plugs – making them more responsive. Once these have been cleaned thoroughly,
reconnecting and resetting your trailer braking system should resolve this message
on your truck’s dash.
Brake Relays
Trailer brake relays send the signal to activate brakes when someone steps on their
brake pedal, making this device common on horse trailers, large boat trailers and
other types of trailers; RVs, campers and enclosed trailers also use them.
Failure of a brake relay could be responsible for your service trailer brake system
message on your truck, while a blown fuse could also be a culprit. Driving under
such conditions may not be safe, and should be avoided until an issue can be
addressed and resolved.
Find your brake relay in the power distribution center or fuse box under your hood
by searching for an FMM/MCase (park lamp fusing) fuse, which may also act as anti-lock brake relay in some vehicles.
Brake Controller
A brake controller monitors the amount of pressure applied to a trailer’s brakes,
helping you avoid overusing them and protect their longevity from unnecessary wear and tear.
Brake controllers aren’t an exact science, so sometimes you may require making
changes. To reset the system, first remove the trailer wheel in order to gain access
to the adjusting nut. Use a flat screwdriver or penetrating oil if the locknut becomes
tight or is rusty, and loosen or tighten accordingly.
Next, locate and twist clockwise the adjusting nut located within your truck’s user
manual to reset its system.