BENDIX TCH-003-049A User Manual

Technical Bulletin

Bulletin No: TCH-003-049 Effective Date: 10/18/05 Cancels: N/A Page: 1 of 4

Subject: Flood Damage: Bendix Recommended Procedure for Power Vehicles

that may have been Submerged.

This Bulletin provides a recommended procedure for the inspection and (where possible) reconditioning of the air
brake control system components on power vehicles (Trucks, Tractors, and Buses) that have been submerged
in flood waters. See Bulletin TCH-003-048 for Trailer and Dolly recommended inspections.

CAUTION: Take all appropriate safety measures when working in conditions where hazardous
waste, etc. may be present, including appropriate eye protection, gloves and masks. See the General

Precautions section at the end of this Bulletin for recommended standard maintenance safety practices for
normal conditions.

SALT (SEA) WATER IMMERSION

Bendix Commercial Vehicle Systems LLC recommends immediate replacement of
all power vehicle pneumatic air brake valves that have been submerged in salt (sea)
water to avoid any immediate or future operational issues as a result of internal corrosion.

Due to the extremely corrosive nature of salt water and the inherent removal of valve
lubrication, sudden and premature valve malfunction can result. Vehicle components
recommended to be replaced include air compressors, reservoir(s), relay valves, spring
brake valves, ABS relay-modulators and brake actuators. If the air brake components

are being replaced, there is no need to conduct the Air Brake System Inspections below,
instead go to the sections for ABS System inspections and also the “General” heading
for steps in restoring the vehicle to service.

AIR BRAKE SYSTEM INSPECTION

In all other cases where the power vehicle or
components have been submerged in fresh water,
the recommended steps depend upon what is found
during the following inspections. If the vehicle was in a
coastal area and you are not certain whether the water
submergence was by fresh water or salt (sea) water,
our recommendation is to follow the guidelines for salt
water submergence above. A separate section in this
Bulletin covers inspections for the ABS system.

While it is not the scope of this Bulletin to address
anything beyond the air brake control system of
the power vehicle, as a useful first step, Bendix
Commercial Vehicle Systems LLC recommends that
a thorough power-washing of the power vehicle,
including the foundation brakes, will assist the
technician in determining the condition of the vehicle
components. Follow usual chassis re-lubrication
measures (including re-greasing of slack adjusters)
after power-washing.

To check for evidence of water or contamination

mark and remove the connectors at the first valve in
the system from the front. Inspect the valve for water
and contaminants. Carefully use air pressure to blow
air through the hoses and watch for evidence of water
or contamination. CAUTION: Take all necessary

precautions for safety of the technician and others
in the work area during this procedure, including
use of appropriate eye protection.

If evidence of water or contamination is found, go

to Section A below.

Continue to inspect all the valves in the air brake
system, removing one control (or supply in the case of
quick release valves) and delivery hose from each of
the valves and inspect to determine if there is evidence
of water or contamination. If evidence of water or

contamination is found, follow the instructions
under Section A.

If no evidence of water or contamination is found in
any of the valves or hoses, follow the braking system
inspections shown in Section B.

,

continued over

Bulletin No: TCH-003-049 Effective Date: 10/18/05 Cancels: N/A Page: 2 of 4

Section A. Power vehicle air brake systems
with evidence of water or contamination

Once water or contamination has entered into any
of the air brake components (for example through
the exhaust valves, etc.), removal of all the water or
contamination is not possible without total disassembly
of the components. Therefore Bendix recommends

that all pneumatic air brake components be
replaced (including the air compressor, air dryer,

reservoir(s), relay valves, spring brake valves, ABS
relay-modulators, tractor protection valves and brake
actuators). This action is necessary to avoid any
immediate or future operational issues as a result of
internal corrosion and water migration.

See the “ABS Systems” section below for ABS system
checks and the “General” subheading below for hose
cleaning/replacement recommendations.

Section B. Power vehicle air brake system
with no evidence of water/contaminants
found.

Power vehicles with only limited exterior exposure to
fresh water can be returned to service after having
their air brake system thoroughly tested. Include
checks to verify that the parking and emergency
brakes apply and release and that the reservoirs
charge with minimal leakage (See General section
at the end of this Bulletin for details of a leakage
test). Check that the application and release of the
power vehicle service and parking brakes occur with
no perceptible lag through the full range of normal
service brake applications. Where applicable (for
towing vehicles), make certain that the trailer supply
and trailer service glad hands apply and release the
trailer brakes fully with no perceptible lag.

heater for operation for models where it is not part of
the purge valve assembly and replace as needed.

For ABS system checks, see “ABS Systems” section
below. Vehicles with normally-functioning air brake
systems can be returned to service. Have all air dryers
regularly serviced to aid in removing any residual
moisture from the vehicle air brake system.

In addition, all reservoirs should be pressurized and
then slowly drained using their drain valves to remove
any contents. After 30 days retest the vehicle (see
next section).

30 DAY RETEST

Bendix recommends that power vehicles that
do not show any internal evidence of water or
contamination be retested 30 days after the vehicle
has been returned to service. Bendix recommends
that the vehicle be re-tested for operation, leakage,
and contamination, and that a diagnostic check
of the ABS system be carried out (see below).

Use diagnostic software (e.g. Bendix

®

ACom5™
PC-Diagnostic Software) to look for any present or
intermittent trouble codes stored in the ABS ECU.
Any air brake components found inoperative should
be replaced.

ABS SYSTEMS

ABS systems on power vehicles are comprised of
an ABS wire harness, wheel speed sensors, and an
Electronic Control Unit (ECU) — in some cases with
an attached relay/modulator valve assembly (see
above for air brake valve inspections).

With a parked vehicle (chocked wheels), test the
Tractor Protection function by disconnecting the
service glad hand. Caution: Have a technician hold

the tractor service glad hand to prevent damage
as a result of the test - since it may whip. With the

red Trailer Air Supply button in, make a service brake
application. The tractor protection function should
detect that the glad hand is unattached, and pop the
red button out, protecting the tractor from further air
loss through the glad hand.

Replace any non-functioning valves.

Following the thorough cleaning of the air dryer it
is recommended to service the unit by replacing
the purge valve assembly and desiccant cartridge
irrespective of the level of contamination found, as long
as the housing is not physically damaged. Check the

FRAME-MOUNT

ECUS

CAB-MOUNT

ECU

FIGURE 1 - EXAMPLES OF BENDIX FRAME AND CAB­MOUNT ECUS