PARKING BRAKE CONTROL

 

INFORMATION

 

TYPE OF PARKING BRAKE MECHANISM

 

Many of the checks in this sub-section are based on the assumption that the parking brake is a ratchet type hand lever. For vehicles with foot-operated or electronic parking brakes the “Method of Inspection” detailed will need to be ignored or varied depending on the particular type.

 

Hydraulic parking brakes as a sole means of operation are not acceptable on vehicles first used on or after 1 January 1968. However they may be used to assist the application or release of a mechanical brake.

 

An electronic parking brake (EPB), although applied electronically, must be maintained in operation by direct mechanical means. This mechanism may be within the brake caliper or within the motor/gear assembly, so cannot be readily seen.

 

An Electronic Parking Brake (EPB) may apply automatically in certain conditions, such as when the driver’s door is opened. Examiners should be aware of this throughout various aspects of the test.

 

METHOD OF INSPECTION

 

1. Check that the vehicle has a parking brake designed to prevent

 

• • at least two of the wheels from turning, or

 

• • with a three-wheeled vehicle, all the wheels on an axle from turning (one wheel if only one wheel is on that axle).

 

2. Check the method of operation.

 

3. While sitting in the driver’s seat, check the presence, security and condition of the parking brake lever or control.

 

4. With the brake lever in the ‘off’ position:

 

1. 1. Check the amount of side play in the lever pivot by moving the lever from side to side.

 

Note:  

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

 

1. 2. Check the security of the lever and pawl mechanism pivots, their associated mountings and the presence and effectiveness of retaining and locking devices.

 

Note: 

Items not possible to check fully from the drivers seat should be checked from beneath the vehicle, opening the bonnet to inspect fully the parking brake mechanism might also be necessary.

 

5. 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.

 

6. When the brake is fully applied:

 

1. 1. knock the top and each side of the lever and check that the lever stays in the ‘on’ position,

 

1. 2. check that the lever is not at the end of its working travel and that there is no fouling of adjacent parts,

 

1. 3. check that the lever is not impeded in its travel.

 

7. On vehicles with an electronic parking brake, operate the switch to release and apply the parking brake and check that a malfunction is not indicated.

 

8. Check the parking brake lever or control for any inappropriate repair or modification.

 

9. Check the condition of the vehicle structure around the mountings of any:

 

1. 1. mechanical parking brake lever mechanism

 

1. 2. electro-mechanical actuator unit.

 

Note: It may be necessary to check the mounting of the parking brake lever or EPB electromechanical actuator unit ‘prescribed areas’ from the vehicle underside when it cannot be checked from the inside the cabin.

 

 

REASON FOR REJECTION

                                                                                                                                    Deficiency Category

 1. The vehicle does not have a parking brake designed to           prevent:

             

1. At least two wheels from turning,          MAJOR

             

2. With a three-wheeled vehicle, all the wheels on an axle     MAJOR from turning.

             

2. For vehicles first used on or after 1 January 1968 the parking MAJOR brake is not capable of being maintained in operation by direct mechanical action only.

             

3. The brake lever or control:     

             

1. 1. Missing      DANGEROUS

             

1. 2. Insecure    MAJOR

             

1. 3. Defective or located so that it cannot be satisfactorily          DANGEROUS operated.

             

                4.                                                                                                                                  

             

1. 1. Side play in the brake lever pivot to the extent that the MAJOR pawl may inadvertently disengage.

             

1. 2. The lever or pawl mechanism pivots and their        MAJOR

associated mountings are insecure or a locking or retaining device is insecure or missing.

      

1. 3. The lever pivot or ratchet mechanism worn but not            MINOR

affecting its functionality 

             

                5.     The pawl spring is not pushing the pawl positively into the                    MAJOR

ratchet teeth or the ratchet has broken, or excessively worn, teeth.

             

                6.                                                                                                                                  

                         

                             a.     When knocked, the lever is not held in the ‘on’ position.               MAJOR

           b. When the brake is fully applied there is no possibility of  further travel of the lever because the lever is:

             

•          at the end of its working travel on the ratchet, or           MAJOR           

•       fouling adjacent parts of the vehicle.	MAJOR
c.      The lever is impeded in its travel.	MAJOR
7.     Electronic parking brake warning indicates a malfunction.	MAJOR
Note:
An EPB malfunction may alternatively be indicated by a message on the dashboard.
8.      A parking brake lever or control inappropriately repaired or modified.	MAJOR
Note: Deliberate modification which significantly reduces the original strength, excessive corrosion, severe distortion, a fracture or an inadequate repair of a load bearing member or its supporting structure or supporting panelling within 30 cm of a parking brake mechanism or any associated mounting(s), that is, within a ‘prescribed area’, see Appendix A.