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TM 5-4210-230-14&P-1
VEHICLE OPERATION
BRAKE ANTILOCK MONITOR (Warning) LIGHT
A  satisfactory  antilock  system  is  indicated  each  time
the   ignition   key   switch   is   turned   to   either   "ON"   or   "RUN"
position 
with 
the 
antilock 
warning 
light 
momentarily
illuminating, followed by the light going out and remaining off.
If  the  warning  light  should  remain  "ON"  a  problem  is
indicated in the antilock control system.  Should this condition
occur, the service brakes will function in the normal manner;
however,   the   vehicle   will   not   have   the   added   safety   and
advantage of the antilock.
If the antilock warning light comes on and stays on, the
antilock    system    should    have    an    "Ignition    Cycle    Check"
performed to determine if all or any computer modules and air
control valves are operating satisfactorily.  Refer to VEHICLE
MAINTENANCE   "Brake   Antilock   System"   for   Ignition   Cycle
Check.
As  the  vehicle  is  driven  about  24  km  (15  mph)  the
antilock warning light should remain "OFF".  If the light should
come  "ON"  and  remain  on  above  24  km  (15  mph),  a  wheel
sensor problem may exist.  Excessive spin on one drive wheel
relative  to  the  other  on  some  axles  may  cause  the  monitor
light to go "ON".  To correct this condition, the ignition switch
must be turned "OFF" and back "ON" to reset the system and
correct the condition.
If wheel spin is not the cause of the light remaining on,
one  or  more  of  the  sensors  could  be  the  problem.    Refer  to
VEHICLE  MAINTENANCE  "Brake  Antilock  System"  for  quick
trouble shooting of antilock system.
BRAKE PEDAL
When making a stop for a traffic light or going down a
long grade, do not "fan" the air brake pedal as this wastes air
pressure.      On   long   grades,   use   snubbing   "on-off"   brake
application to reduce the possibility of extreme heat and wear
to  the  brake  lining.    A  good  policy  to  follow  is  to  downshift
your   vehicle   on   long   grades   to   obtain   maximum   engine
assistance in reducing vehicle speed.  The best way to make
a stop is to apply the brakes as hard at first as the road and
load   conditions   will   permit   and   then   gradually   reduce   the
pressure, so that at the end of the stop there is sufficient air
pressure to hold the vehicle.
BRAKES PARKING
If   both   air   systems   fail   or   are   depleted   the   spring
brakes apply.
To release, repair air leak and recharge system to 483
kPa (70 psi).  If leak cannot be repaired and the vehicle must
be moved, the spring brake must be manually released.
CAUTION
To  avoid  personal  injury  or  property  damage
when  manually  releasing  the  spring  brakes,
be  sure  to  block  the  wheels  so  that  vehicle
cannot  move  when  the  brakes  are  released.
For 
towing, 
make 
sure 
the 
vehicle 
is
connected  or  secured  to  tow  vehicle  before
releasing the spring brakes.
BRAKE RELEASE (Parking)
ANCHOR LOK SPRING BRAKE
In the event it is necessary to move the vehicle after an
emergency  application  (before  air  pressure  can  be  restored),
the 
emergency 
parking 
spring 
can 
be 
compressed
mechanically  to  release  the  brake.    A  release  stud  "spring
caging  tool"  is  furnished  with  the  brake  chamber  assembly.
The release stud engages in the spring pressure plate and its
nut is tightened to compress "cage" the spring and release the
brake.
Apply a light coat of Never Seeze to the threads of the
release  stud  to  avoid  any  unnecessary  wear  of  the  threads.
Remove the access plug from the end of the spring chamber.
Insert  the  release  stud  through  the  opening  in  the  chamber
and into the spring pressure plate.
Turn the release stud 1/4 turn to engage the tangs on
the release stud into the slot in the pressure plate.  Install the
nut on the release stud.  Be sure tang on release stud stays
engaged  with  slot  on  pressure  plate  while  installing  the  nut.
Tighten the nut with a wrench to compress the spring.
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