Bendix Hydro-Max® Brake System Inspecting (Front-Engine Diesel Chassis); Brake Caliper Slide Pin Lubricating, Bosch Brakes (Front-Engine Diesel Chassis); Brake Inspecting - freightliner MC Maintenance Manual

42
42–07 Bendix Hydro-Max®
Brake System Inspecting
(front-engine diesel
chassis)
1. Check the fluid level in the hydraulic brake fluid
reservoir. If needed, fill the reservoir up to the
ridge that surrounds the reservoir. See
Use only heavy-duty brake fluid, DOT 3.
07/31/2015
A. Open caps and check fluid level.
B. Fill to this level.
Fig. 9, Hydraulic Brake Fluid Reservoir
2. Check all hydraulic lines and fittings for damage,
leakage, or looseness.
Replace damaged or leaking components, and
tighten loose fittings.
3. Check the brake module for leaks. If leaks are
found, repair or replace the brake module. See
Group 42 of the Recreational Vehicle Chassis
Workshop Manual for replacement instructions,
or take the vehicle to an authorized Freightliner
Chassis dealer.
42/8
Fig.
B
A
f460513b
4. Check the electrical connections and harnesses.
Make sure the connectors are fully seated and
the harnesses are not chafed or cut. Repair or
replace any damaged harness. Disconnect any
loose connectors and inspect the terminals for
corrosion. If corrosion is present, replace the ter-
minals. If corrosion is not present, reconnect the
connector.
5. Check the fuse for the hydraulic brake booster
9.
pump, as follows.
5.1 Open the cover to the main power distri-
bution module (PDM).
5.2 Pull the fuse in position F6 for the Hydro-
Max relay.
5.3 Inspect the relay to make sure the fuse is
not damaged. If the fuse is damaged, in-
stall a new fuse. If the fuse is not dam-
aged, install the fuse in position F6.
5.4 Close the PDM cover.
6. Check the operation of the Hydro-Max brake
booster, as follows.
6.1 With the ignition off, depress the brake
pedal and listen for the back-up motor to
engage. Also note that the pedal force
relieves; the pedal should depress easily.
6.2 With the ignition on, engine running, park-
ing brake released, ensure that the
BRAKE warning indicator light is not on.
This is a dual indicator and indicates that
the parking brake is set, and warns if
there is a hydro-max failure other than
loss of back-up motor power.
42–08 Brake Caliper Slide Pin
Lubricating, Bosch
Brakes (front-engine
diesel chassis)
NOTE: There is no set maintenance interval for
lubricating pin-slide hydraulic disc brake cali-
pers.
Apply 1/8 oz (3.5 g) Aeroshell grade 5 grease to
each of the two guide pin and guide pin bore sets.
See the Bosch Pin Slide Disc Brakes Service Manual
for additional information.
Recreational Vehicle Chassis Maintenance Manual, July 2018
Brakes