of parking brake mechanism
this sub-section, it is assumed that the parking brake
is applied by a hand lever.
vehicles with foot-operated parking brakes the “Method
of Inspection” detailed will need to be varied for the
Check that the vehicle has a parking brake designed to
least two wheels from turning, or with
a three-wheeled vehicle, at least one wheel from
The vehicle does not have a parking brake designed to prevent
least two wheels from turning with
a three-wheeled vehicle, at least one wheel from turning
Check the method of operation
For vehicles first used on or after 1 January 1968 the parking
brake is not capable of being maintained in operation by
direct mechanical action only.
certified by the London Science Museum as being designed
before 1 January 1905 and constructed before 31 December
1905 do not require a parking brake.
Examine the condition of the brake lever and its location.
The brake lever is defective or so located that it cannot
be operated satisfactorily.
With the brake lever in the “off” position
note the amount of side play in the lever pivot by moving
the lever from side to side
Some vehicles have sideways movement of the parking brake
lever when new. Movement is a reason for rejection
only when the
pawl is moved clear of the ratchet, and the
brake does not hold in the ‘on’ position
side play in the brake lever pivot to the extent that the
pawl may inadvertently disengage
check the security of the lever and pawl mechanism pivots,
their associated mountings and the presence and effectiveness
of retaining and locking devices
Items not possible to check fully from the driver’s seat
should be checked from beneath the vehicle
the bonnet to inspect fully the parking brake mechanism
might also be necessary.
the lever or pawl mechanism pivots and their associated
mountings are insecure or a locking or retaining device
is insecure or missing
Without operating the pawl mechanism, apply the parking
brake slowly and check the effective operation of the pawl
mechanism by listening for definite and regular clicks as
the pawl moves over the ratchet teeth.
The pawl spring is not pushing the pawl positively into
the ratchet teeth or the ratchet has broken, or excessively
When the brake is fully applied
knock the top and each side of the lever and check that
the lever stays in the “on” position
when knocked, the lever is not held in the “on” position
check that the lever is not at the end of its working travel
and that there is no fouling of adjacent parts
when the brake is fully applied there is not possibility
of further travel of the lever because the lever is
the end of its working travel on the ratchet, or
adjacent parts of the vehicle
check that the lever is not impeded in its travel
the lever is impeded in its travel
Check the vehicle structure around the mounting of the parking
brake for fractures, cracks, corrosion and distortion.
It may be necessary to check the parking brake lever mounting
‘prescribed area’ from the vehicle underside when it cannot
be checked from the inside.
Deliberate modification which significantly reduces the
original strength, excessive corrosion, sever distortion,
a fracture or an inadequate repair of a load bearing member
or its supporting structure or panelling within 30cm of
a parking brake mounting, that is, within a ‘prescribed
area’, see Appendix C.