Ford Falcon. Manual — part 61

206-00-6

Brake System — General Information

206-00-6

DIAGNOSIS AND TESTING

Rotor Wear and Runout

Brake System

Remove the wheel to inspect the rotor.

Special Tool(s)

Check the rotor for scoring. Minor scores need not

Vacuum Pump

be removed. If the rotor is excessively scored,

416-D002 (D95L-7559-A) or

refinish it in accordance with the Specifications or

equivalant

replace the rotor.
When checking front rotor runout, be sure to take

the wheel bearing end play into account. Remove

the rotor if necessary.
Front wheel bearing end play is critical and must

be within specifications.

Inspection and Verification

To check the rear rotor run-out either apply a load

to the end of the axle shaft to remove the end

WARNING: Brake fluid contains polyglycol

float in the bearing or remove the axle shaft and

ethers and polyglycols. Avoid contact with eyes.

rotor assembly from the housing and check the

Wash hands throughly after handling. If brake

run-out by mounting the axle on its centres.

fluid contacts eyes, flush eyes with running water

Clamp a dial indicator to the caliper housing so

for 15 minutes. Get medical attention if irritation

that the stylus contacts the braking surface of the

persists. If taken internally, drink water and

rotor approximately 32 mm from the outer edge

induce vomiting. Get medical attention

for a front rotor or 3mm from the outer edge for a

immediately. Failure to follow these instructions

rear rotor.

may result in personal injuiry.

Rotate the rotor and take an indicator reading. If

the total lateral run-out exceeds 0.08 mm for a

CAUTION: Do not spill brake fluid onto

front rotor or 0.05 mm for a rear rotor, resurface

painted surfaces. If spilled, wipe it up

or replace the rotor.

immediately.

Refer to Specifications section for refinishing

NOTE: Always check the fluid level in the brake

specifications. Refer to Section 206-03 or Section

master cylinder before carrying out the test

206-04 for information regarding rotor

procedures. If the fluid level is not above the MIN line,

replacement.

add High Performance Motor vehicle brake fluid

meeting Ford specification ESZ-M6C55-A or

Disc Thickness Variation

equivalant Super DOT4 fluid.

This is the variation in thickness between the two

NOTE: Prior to carrying out any diagnosis, verify that

braking surfaces of the rotor measured

the brake warning indicator is functional. Apply the

circumferentially.

parking brake. If the brake warning indicator does not Disc thickness variation may cause a pulsating pedal

illuminate, refer to Brake fail warning light component

or noisy operation.

test.

Two methods may be used to measure thickness

NOTE: The primary indicators of brake system

variation.

concerns are a change in the feeling through the

A micrometer can be used to measure the rotor

brake pedal, the brake warning indicator, and the

thickness at 12 points approximately 30 degrees apart

brake fluid level. If a problem exists, refer to the

and 25 mm from the outer edge of the rotor.

following diagnosis guide.

The other method is to mount the rotor on a precision

lathe designed for machining disc brake rotors. Attach

Pad Wear

two dial indicators, one each side of the rotor, so that

Remove the wheel to inspect the pads. Refer

the stylus of each indicator contacts the rubbing

Warning under Service Precautions.

surface approximately 25 mm from the outer edge of

the rotor.

If a lining has worn to a thickness of 1.0 mm at

any one of three measuring locations or if there is Zero both indicators and rotate the rotor while

more than 3 mm taper from end to end replace all watching both dials. If the total readings of both

(4) pad assemblies on both front or both rear

indicators exceed the specified limit for thickness

wheels to maintain even braking. Refer to Section variation, the rotor must be refinished or replaced.

206-03 or Section 206-04 for replacement of

parts.

G17361 en

206-00-7

Brake System — General Information

206-00-7

DIAGNOSIS AND TESTING (Continued)

Rotor Thickness and Refinishing

Rear Disk Brake Resurfacing Limits

Measure the thickness of the rotor to determine if it is

within the specifications.
Use a disc brake lathe to refinish the disc brake

rotors. Refer to Specifications for the remainder of the

refinishing specifications.

Front Disk Brake Resurfacing Limits

Symptom Chart

Symptom Chart

Condition

Source

Action

Excessive effort needed to depress

Brake pedal binds at pivot

INSTALL a new brake pedal

brake pedal or has a rough or raspy or
sticky feel

CHECK the brake booster and REFER

Brake booster

to the Booster Section.

Return Booster spring damaged or

CHECK the brake booster and REFER

incorrectly positioned

to the Booster Section.

Worn or damaged brake pedal

INSTALL a new brake pedal.

Foreign object caught in brake pedal

CHECK the brake pedal.

CHECK the brake booster and REFER

Brake pedal does not return freely

Weak or broken Booster return spring

to the Booster Section.

Foreign object caught in brake pedal

CHECK the brake pedal.

No response from the brake lights

CHECK the connection between the

Unconnected light switch

when the brake pedal is pressed

light switch and the light.

Faulty brake switch flag

INSTALL a new brake pedal.

CHECK the light switch. REPLACE or

Incorrect position of the light switch

CHANGE light switch.

No response from the cruise control

CHECK the connection between the

Unconnected cruise switch

when the brake pedal is pressed

cruise switch and the cruise control.

Faulty brake switch flag

INSTALL a new brake pedal.

CHECK the cruise switch. REPLACE

Incorrect position of the cruise switch

or CHANGE cruise switch.

G17361 en

206-00-8

Brake System — General Information

206-00-8

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

No deceleration when the brake pedal

Connection between the Booster rod

CHECK connection
PUT the booster rod in the cantilever

is pressed

and the brake pedal

pin of the brake pedal if the booster
rod is not connected to the cantilever
pin of the brake pedal.

CHECK Booster clip, CHANGE it if

necessary.

CHECK the brake booster and REFER

Faulty booster

to the Booster Section.

CHECK brake pedal pad and

Discomfort on Brake pedal

Brake pedal pad worn or loose

CHANGE it if necessary.

Padal feel

Brake Pedal Not Returning on Release

Go to PinPoint Test B

Braking System Diagnosis. Refer to

Excessive Pedal Travel

Section 206-00.

"Raspy" feel

Go to PinPoint Test B

Pedal Binding at Pivot

Go to PinPoint Test A

Replace Brake Pedal Pad. Refer to

Pedal Pad Worn

Section 206-00.

Obstruction at Pedal

Go to PinPoint Test B

Braking System Diagnosis. Refer to

Poor braking efficiency

Faulty Brake Booster

Section 206-00.

Refer to Section 206-03 and Section

Brake Disc Pads Worn

206-04.

Booster Rod Disconnected

Go to PinPoint Test ???

Vacuum Poor, Leaking or

Braking System Diagnosis. Refer to

disconnection at the Brake Booster

Section 206-00.

Cruise control not turning off when

Braking System Diagnosis. Refer to

Brake Master Cylinder Leaking / Faulty

brake applied

Section 206-00.

Cruise Control Switch Faulty / Plug

Go to PinPoint Test D

Disconnected

Stop Lamp Switch Faulty / Plug

Go to PinPoint Test C

Disconnected

Adjustable brake pedal

Cannot Adjust Pedals

Go to PinPoint Test E

Faulty Memory

Go to PinPoint Test E

Go to Section 310-02, Pinpoint test 5

Pedal "Step Over" Height Incorrect

& 6.

Stop lamp switch

Stop Lamp Switch Faulty

Go to PinPoint Test C

Symptom Chart-(For adjustable pedal box only)

Condition

Source

Action

CHECK the connection between the

Unable to adjust the brake pedal

Unconnected Adjustment motor

motor and the MSC

Disengaged adjustment cable in the

RECONNECT adjustment cable

brake pedal

Faulty Potentiometer (Memory Pedal

REPLACE

potentiometer

Box Only)

Faulty memory settings (Memory

RESET

memory

Pedal Box Only)

G17361 en

206-00-9

Brake System — General Information

206-00-9

DIAGNOSIS AND TESTING (Continued)

Condition

Source

Action

Incorrect step over between brake

Refer to disassembly and assembly

Incorrect-adjustment

instructions: Indexing pedals ( Section

pedal and accelerator pedal

206-06)

NOTE: Do not stall through accelerator transmission.

and brake chatter. For each of the symptoms

encountered, check and eliminate the causes. To

Components Tests

check for brake chatter or surge apply the brakes

lightly from approximately 80 km/h.

Brake Booster

If the preliminary tests show that the booster is

With the transmission in neutral, stop the engine and

inoperative or if a hard pedal condition exists the

apply the parking brake. Depress the service brake

trouble may be caused by vacuum leakage.

pedal several times to exhaust all vacuum in the

Disconnect the vacuum line at the booster, remove

system. Then, depress the pedal and hold it in the

the vacuum manifold and check valve assembly and

applied position. Start the engine. If the vacuum

look for a sticking or faulty check valve. Check all

system is operating the pedal will tend to fall away

vacuum connections for leakage or obstruction. Check

under foot pressure and less pressure will be required all hoses for a leaking or collapsed condition. Repair

to hold the pedal in the applied position. If no action is or replace as necessary.

felt, the vacuum booster system is not functioning.

If the trouble persists, replace the vacuum booster.

Refer to the Diagnosis Guide.

The booster is not a serviceable item and if found

defective must be replaced.

For booster removal and installation procedures refer

to Section 206-07.

Brake Master Cylinder

For cleaning and inspection refer to the following

pages in this part.

CAUTION: The braking system should be

filled with a special high boiling point (280

°C)

Brake Fail Warning Light Test

brake fluid which must not be contaminated with

Turn the ignition key to the ignition ON position,

ordinary brake fluid. Ensure only approved brake

the warning lamp should not illuminate. If the lamp fluid is used (refer Specifications section).

illuminates a defect exists in the system and may

Brake fluid is hygroscopic, which means that it takes

be:

in moisture from the air. Water-affected brake fluid

a pressure differential in the hydraulic system. has a reduced boiling point. The heat generated by

a defective differential valve switch (where

repeated heavy braking causes the fluid to boil at a

fitted).

lower temperature, resulting in loss of braking. The

water also helps corrosion start in the braking system.

grounded switch wires.

The brake fluid must be replaced at least every two

Turn the key to the START position, the lamp

years if the brakes are to remain fully effective.

should illuminate while the key is held in this

If brake fluid is spilt on paintwork, the affected area

position. If the lamp does not light check the bulb

must be washed down with cold water immediately.

and wiring for defects.

Road Test

The vehicle should be road tested only if the brakes

will safely stop the vehicle. Apply the brakes at a

speed of 40- 50 km/h to check for any of the trouble

symptoms listed in the Diagnosis Guide with the

exception of those resolved in the preliminary tests

G17361 en