28
MAINTENANCE
Air Brakes
Air Brakes - General
Etnyre trailers are equipped with cam actuated
brakes. Braking force is supplied by air pressure in
the brake chamber, which pushes a pushrod against
the end of the slack adjuster. The slack adjuster rotates
the camshaft, which forces the brake shoes against the
brake drum.
Figure 19. ABS Electrical Connections
E
C
U
BLUE
WHITE
RED
JUNCTION BOX
4
5
LEFT
SIDE OF TRAILER
ABS STANDARD ELECTRICAL DIAGRAM
Operating Checks
During road stops, check the brake drums for
heating.
WARNING
Proceed cautiously. Malfunctioning or
misaligned brakes can cause the drum
to become extremely hot. Do not operate
the vehicle until the problem causing the
overheating is corrected.
A cool brake drum may indicate an inoperative brake.
A series of tests are outlined on page 26.
Brake Assembly
Examine the brake linings visually to locate the lining
showing the greatest amount of wear.
CAUTION
Do Not
allow the linings to wear thin enough so
the lining bolts or rivets contact the drum.
S
S
S
S
Sensor Cable
ROADSIDE
CURBSIDE
FRONT
ECU/Relay Valve
Priority Valve
Reservoir
Brake Chamber
Brake Chamber
Emergency Line (Supply)
Service Line (Signal)
Brake Chamber
Axle
Axle
Brake Chamber
Sensor Cable
Sensor Cable
Figure 20. ABS Brake Air Supply System