TSE DPT40-B, Owner'S Manual

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Braking Systems - Hydraulic
Troubleshooting Guide
Brakes are slow to respond
1. Re-bleed the trailer brakes and actuator.
2. If the trailer is equipped with drum brakes, readjust the
drum brakes to the brake manufacture's recommended
running clearance.
3. Slow response can be caused by trailer wiring that is too
small.
4. For trailers where the E/H unit is located less than 10 feet
from the tow vehicle, 12 gage wire is recommended for the
black and white wires between the tow vehicle and the E/H
unit. All other wires should be a minimum of 16 gauge.
5. For trailers where the E/H unit is located more than 10 feet
from the tow vehicle, 10 gage wire is recommended for the
black and white wires between the tow vehicle and the E/H
unit. All other wires should be a minimum of 16 gauge.
6. Slow response can be caused by improper adjustment of
the brake controller. On inertia-based electronic brake
controls, adjust the pendulum (inertia sensor) to a more
aggressive setting and/or increase the gain setting.
Unit will not run when the ignition is on and the brake pedal is
depressed
1. Verify that the trailer and tow vehicle are wired as detailed
on the electrical schematic.
2. With the ignition switch on and the brakes not applied, you
should have 12-13 volts between the black and white wires
on the E/H unit.
3. Clean and replace the ground between the trailer and the
E/H unit.
4. Test operation of the unit using the breakaway test
procedure.
Breakaway test procedure - do not leave the breakaway switch
pulled for more than two minutes during any of the steps outlined
below
1. Pull the breakaway switch on the trailer.
2. If the unit runs and builds pressure, that indicates the