SECTION 12: BRAKE AND AIR SYSTEM
10
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version – Rev.2 April 2016)
conditions of having a vehicle speed greater
than 2 mph and the engine running.
The solenoid remains energized simultaneously
with activation of the rear stop lights to heat up
air output to prevent it from freezing. However,
Multiplex programming will ensure that the
solenoid remains energized for at least of 45
seconds but not longer than 5 minutes.
8.1 MAINTENANCE
The Consep requires little maintenance during
its long service life. The Consep must be
inspected periodically for proper operation. The
interval between inspections is determined by
the type of service (every 12,000 miles for City
Transit). High compressor duty cycles and high
temperatures can cause a buildup of carbon in
the condenser, drain valve and filter. This
contamination must be removed for proper
operation.
For more information on the periodic inspection,
refer to
Haldex Consep Condenser Separator,
Installation, Maintenance & Inspection
L31167
included on your technical publications
CD.
9. AIR
LINES
Copper piping, nylon-reinforced tubing, and
flexible hoses are used to connect the units in
the pneumatic system, including air brake
system, suspension system and accessory
systems such as the entrance door, fresh air
damper cylinder, air horns, etc. Furthermore, the
nylon tubing is color coded to ease identification.
Refer to the following table for the complete
color identification code. Service instructions for
each type of air line are also provided under the
applicable headings.
Color
Circuit
Green
Primary Brake System and Supply
Red
Secondary Brake System
Brown
Parking / Emergency Brake System
Yellow Compressor
Governor
Signal
Black
Accessories Air System
Blue Suspension
9.1 FLEXIBLE
HOSES
A flexible hose is used normally where it is
impractical to use copper or nylon tubing due to
constant flexing during operation, such as brake
chamber hoses. Hose connections should be
tested for leakage at least every 6,250 miles
(10 000 km) or twice a year, whichever comes
first and tightened or replaced if necessary. Any
hose which is chafed, worn or kinked should be
replaced.
Teflon-braided stainless steel hoses used in the
engine compartment must be replaced only with
similar hoses.
9.2 NYLON
TUBING
Nylon tubing is used for air lines in areas where
usage of this material is suitable. Nylon tubing is
flexible, durable, and weather resistant. When
replacing an air line, use nylon tubing only
where it has been used previously.
Nylon air lines must never be routed in areas
where temperature could exceed 200
o
F (93
o
C).
CAUTION
Nylon air lines should be used to replace
existing nylon lines only, and must comply
with the color identification code to ease
pneumatic system troubleshooting.
9.3
AIR LINE OPERATING TEST
If any trouble symptom such as slow brake
application or slow brake release indicates a
restricted or clogged air line, disconnect the
suspected tube or hose at both ends and blow
through it to clear the passage.
Inspect tubing and hose for partial restriction
that may be caused by dents or kinks. If such a
condition is found, the tubing or hose should be
replaced.
9.4
AIR LINE LEAKAGE TEST
With air system fully charged and the brakes
applied, coat all tubing and hose connections
with a soapy solution to check for air leakage.
No leakage is permitted. Leakage can
sometimes be corrected by tightening the
connection. If this fails to correct the leakage,
new fittings, nylon tubing, copper tubing,
teflon-braided stainless steel and flexible hoses
must be installed as applicable.
9.5 MAINTENANCE
Inspect all lines for cuts, swelling, kinks or other
damage or deterioration. Check for lines being
pinched by other components. Retaining clips
and ties must be in place.
Any support or bracket should be in good
condition and mounted firmly in position. Hose
spring guards should be in usable condition and
