Information
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Method of Inspection
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Reason for rejection
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A.
All types of braking systems
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Vehicles with a smooth brake pedal pad which from manufacture
did not incorporate grooves or the fitting of an anti-slip material
should not be subject to rejection.
The provision of a pedal rubber which is itself an anti-slip material
is not regarded as a reason for rejection if the design pattern
is worn smooth.
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A. All types of braking
systems
1. Check
a. the condition of the brake pedal and brake actuating linkage
(eg, to remote master cylinders)
b. the anti-slip face on the pedal pad
c. the security of the pedal pad to the pedal and the pedal to operating
lever
d. the condition of the pedal bearing or pivot
e. for chafed rods or levers
f. for frayed or knotted cables
g. for any corroded or damaged rod, lever or linkage. Wear in eyes
of relay levers, clevis joints, stationary pins or pivots
h. for abnormal movement of levers, indicating maladjustment or
excessive wear.
2. Examine the vehicle structure near actuating linkage and mounting
points for excessive corrosion, distortion and fracture.
3. On vehicles first used on or after 1st Jan 1968, check that a
brake is applied to all the wheels (this may need to be substantiated
during the brake test).
4. Depress the pedal and check for fouling on parts of the vehicle.
5. Depress the pedal fully and check the position of the pad relative
to the floor.
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1a.The pedal or actuating
linkage fractured, excessively corroded or functionally incomplete
b. the anti-slip provision on the brake pedal pad is missing, incomplete,
loose or worn smooth
c. a pedal pad or operating lever not secured to the pedal
d. excessive side movement of the pedal at right angles to its normal
movement indicating a badly worn pedal bearing or pivot
e. a brake rod or lever reduced in thickness by more than l/3rd
f. a brake cable
. knotted or,
. with wires broken so that the cable is weakened significantly
g. serious weakening of any part due to excessive wear or damage
h. abnormal movement of levers
indicating maladjustment or excessive wear.
2. Deliberate modifications which significantly reduces the original
strength, excessive corrosion, severe distortion, a fracture or
an inadequate repair of a load bearing member, its supporting structure
or supporting panelling within 30cm of an actuating linkage mounting
point, that is, within a "prescribed area" see appendix
C.
3. On vehicles first used on or after 1 January 1968 a brake is
not applied to all wheels.
4. The pedal is fouling parts of the vehicle so that free movement
of the pedal is obstructed.
5.When the pedal is fully depressed there is not enough reserve
pedal movement.
Note: This does not apply to power operated braking systems, providing
the foot valve is fully open before the pedal is fully depressed.
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B. Hydraulic systems (including
Servo Assisted)
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1. Fully depress the pedal twice, first slowly and then rapidly
each time to a point where sustained pressure can be held. Check
for creep and sponginess.
2. If a vacuum servo is fitted, then with the engine off, totally
deplete the stored vacuum by repeatedly applying the service brake.
Fully apply the brake and hold at a constant pressure and whether
the pedal can be felt to travel further when the engine is started.
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1.
a. The pedal tends to creep down while the pedal is held under pressure
b. sponginess indicating air in the hydraulic system
2. No dip can be felt when the engine is started, indicating vacuum
assistance is not working satisfactorily.
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C. Diesel engined vehicles with
high servo boost
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This Inspection applies to:
All diesel engined vehicles where pedal creep has been detected
when pressurising the brakes with the engine running.
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1. Check the brake fluid level in the reservoir then pump the
brake pedal several times and check that the fluid level in the
reservoir is unchanged.
2. With the vacuum depleted ensure the pedal is not spongy or does
not creep.
3. With servo assistance fully depress the pedal.
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1. After several applications of the brake pedal the fluid level
in the reservoir has decreased.
2. With the vacuum depleted the pedal is spongy or creeps.
3. With servo assistance the pedal creeps down and touches the floor.
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D. Full power hydraulic braking
systems
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On some vehicles the low vacuum warning light will illuminate
as soon as the ignition is switched on. In these circumstances it
is not a reason for rejection unless the warning light stays on
after the engine has been started
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1. Check that a warning device is fitted.
2. Check whether a warning device fitted is audible or visible to
driver.
3. With the engine switched off, repeatedly apply the service brake
until the warning device operates. Check that at least two further
applications of the brakes are available. In case of doubt the availability
of two further applications can be established when testing the
brakes on a Roller Brake Tester.
Note: Hydraulic braking systems operate quietly. It is normally
necessary to use a roller brake tester to verify that the brakes
are applied.
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1. No warning device fitted.
2.
a. A warning device not visible (or audible) to the driver
b. a visual warning device not readily visible to the driver in
darkness.
3.
a. A warning device not working correctly
b. insufficient reserve pressure to give at least two further applications
of the brakes after the warning device has
operated.
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E. Air and vacuum systems (including
'over hydraulic')
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This inspection applies to:
vehicles registered on or after 1 October 1937.
A vehicle of 3050kg or less unladen, with
. a reservoir coupled direct to the induction manifold, or
. a reservoir integral in a servo unit
is not necessarily required to be fitted with a warning device.
Warning device
A defective audible warning device is not a reason for rejection
if fitted in addition to an operational visual device.
For vehicles first used on or after 1 April 1983, a defective visual
warning device is not a reason for rejection if fitted in addition
to an operational audible device.
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1. Check that a visual warning device or, as an alternative for
vehicles first used on or after 1 April 1983, an audible warning
device is
a. fitted
b. working correctly
2. Check that any visual warning device is
a. visible from the driving seat
b. illuminated, or otherwise visible from the driver's seat in darkness.
3. For systems fitted with a pressure or vacuum gauge, with the
reservoir at a maximum pressure or vacuum, note the reading on the
gauge and then fully depress the pedal. Keep the pedal depressed
and watch the gauge reading.
Note: All vehicles must also be checked for pressure or vacuum leaks
during the under-vehicle inspection of the brake system.
4. Check that the operation of any air or vacuum powered system
(e.g. wipers etc.) does not adversely affect the operation of the
braking system.
5. By applying the service brake repeatedly, gradually empty the
braking system, and
a. if a gauge is fitted, note that
. the reading on the gauge falls steadily each time the brake pedal
is depressed, and
. when the gauge needle has reached the "warning mark",
there is still enough pressure or vacuum in the system to allow
the brake to be applied at least twice more with pressure or vacuum
assistance
Note: Pressure gauge If the pressure
gauge has no warning mark, use 45psi (3.1 kg/sq cm or 3 bar) as
a reference.
Vacuum gauge
If the vacuum gauge has no warning mark, use 10" to 12"
(25 to 30cm) as a reference.
b. If a warning light or other device is fitted, check that, after
the warning has operated there is still enough pressure or vacuum
in the system to allow the brake to be applied at least twice more
with pressure or vacuum assistance.
6. Completely empty the reservoir by repeatedly pressing the service
brake pedal. Start the engine and if diesel run it at just below
the governed speed or 2000 rpm if petrol. Note the time it takes
for the warning device to stop operating.
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1.
a. A mandatory warning device not fitted
b. a mandatory warning device not working correctly.
2. A visual warning device
a. not visible from the driver's seat
b. not illuminated, or its function not visible from the driver's
seat in darkness.
3. The gauge reading drops whilst the pedal is kept depressed, indicating
a leak
in the brake system.
4. The repeated operation of any ancillary air or vacuum system
completely depletes the stored air or vacuum for the braking system.
5.
a.
Insufficient pressure or vacuum to give assistance to brakes for
at least two or more applications after the gauge has reached the
warning mark
b. Insufficient pressure or vacuum to give assistance to brakes
for at least two or more applications after the warning light or
other device has operated.
6. The time between starting the engine and
. the warning device ceasing to operate, or
. the gauge showing a safe reading
indicates that build-up of pressure/ vacuum is low.
For example
. more than 3 minutes for pressure systems
.1 minute for vacuum systems.
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Issue Date: 10th January 2005
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