Frelander 2. Manual - part 104

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Is the power brake booster valve OK?
Yes

CHECK the brake booster. For additional information, refer to Brake Booster component test in this
section. INSTALL a new brake booster as required.
REFER to:

Brake Booster

(206-07 Power Brake Actuation, Removal and Installation).

TEST the system for normal operation.

INSTALL a new brake booster valve. TEST the system for normal operation.

PINPOINT TEST H : BRAKE LOCKUP DURING LIGHT BRAKE PEDAL FORCE

TEST CONDITIONS

DETAILS/RESULTS/ACTIONS

H1: TEST BRAKE LOCKUP

Road test the vehicle and apply the brake pedal lightly.

Do the brakes lockup?
Yes

GO to H2

Vehicle is OK.

H2: INSPECT BRAKE PADS

Inspect brake pads for contamination, correct installation, damage and type.

Are any concerns found?
Yes

INSTALL the brake pads correctly or INSTALL new brake pads as required.
REFER to:

Brake Pads

(206-03 Front Disc Brake, Removal and Installation) /

Brake Pads

(206-04 Rear Disc Brake, Removal and Installation).

TEST the system for correct operation.

GO to H3

H3: INSPECT BRAKE CALIPERS

Inspect brake calipers for binding, leaking or sticking.

Are any concerns found?
Yes

INSTALL the brake calipers correctly or INSTALL new brake calipers as required.
REFER to: Brake Caliper (206-03 Front Disc Brake, Removal and Installation) /

Brake Caliper

(206-04 Rear Disc Brake, Removal and Installation).

TEST the system for normal operation.

Vehicle is OK.

PINPOINT TEST I : BRAKES DRAG

TEST

CONDITIONS

DETAILS/RESULTS/ACTIONS

I1: ROAD TEST VEHICLE

Road test the vehicle and apply the brakes.

Are the brakes functioning correctly?
Yes

Vehicle is OK.

GO to I2

I2: CHECK BRAKE CALIPERS AND PARKING BRAKE CABLES

Check the front and rear caliper pistons and pins for binding, leaking or sticking and parking brake
cables for sticking/binding.

Do the disc brake caliper pistons and pins bind, leak or stick, or the parking brake cables stick/bind?
Yes

REPAIR or INSTALL new components as required. Test the system for normal operation. Road test
vehicle if necessary.

GO to I3

I3: CHECK BRAKE BOOSTER

Check the brake booster connecting rod alignment and travel.

Is the connecting rod OK?
Yes

Vehicle is OK.

INSTALL a new brake booster.
REFER to:

Brake Booster

(206-07 Power Brake Actuation, Removal and Installation).

TEST the system for normal operation.

PINPOINT TEST J : EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL

TEST

CONDITIONS

DETAILS/RESULTS/ACTIONS

J1: TEST ON ROUGH ROAD

Road test the vehicle on rough road conditions.
Apply the brakes slowly.

Is the brake pedal effort and brake pedal travel normal?
Yes

Vehicle is OK.

GO to J2

J2: CHECK BRAKE FLUID LEVEL

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Check the brake master cylinder reservoir fluid level.

Is the fluid level OK?
Yes

GO to J3

CHECK brake master cylinder reservoir sealing points. For additional information, refer to Brake
master cylinder component test in this section. ADD brake fluid and BLEED the brake system.
REFER to:

Brake System Bleeding

(206-00 Brake System - General Information, General Procedures)

Brake System Pressure Bleeding

(206-00 Brake System - General Information, General Procedures).

TEST the system for normal operation. REPEAT road test if necessary.

J3: CHECK BRAKE PEDAL RESERVE

Run engine at idle speed.
Apply the brake pedal lightly three or four times.
W ait 15 seconds for the vacuum to replenish.
Push down on the brake pedal until it stops moving downward or an increased resistance to the
brake pedal travel occurs.
Hold the brake pedal in the applied position while increasing the engine speed to 2000 rpm.
Release the accelerator pedal.

Does the brake pedal move downward as the engine speed returns to idle?
Yes

GO to J4

CHECK the vacuum to the brake booster.

J4: CHECK THE FRONT WHEEL BEARING ASSEMBLY

Check the front wheel bearing assembly.

Are the front wheel bearings loose?
Yes

INSTALL a new front wheel bearing if damaged.
REFER to:

Front Wheel Bearing

(204-01 Front Suspension, Removal and Installation).

TEST the system for normal operation.

CHECK the front brake discs for thickness variances.

PINPOINT TEST K : SLOW OR INCOMPLETE BRAKE PEDAL RETURN

TEST

CONDITIONS

DETAILS/RESULTS/ACTIONS

K1: CHECK FOR BRAKE PEDAL RETURN

Run the engine at idle while making several brake applications.
Pull the brake pedal rearward with approximately 44.5 N (10lb) force.
Release the brake pedal and measure the distance to the toe board.
Make a hard brake application.
Release the brake pedal and measure the brake pedal to toe board distance. The brake pedal
should return to its original position.

Does the brake pedal return to its original position?
Yes

Vehicle is OK.

GO to K2

K2: CHECK FOR BRAKE PEDAL BINDING

Disconnect the brake booster from the brake pedal. Check the brake pedal to ensure free
operation.

Is the brake pedal operating freely?
Yes

INSTALL a new brake booster.
REFER to:

Brake Booster

(206-07 Power Brake Actuation, Removal and Installation).

TEST the system for normal operation.

REPAIR or INSTALL new brake pedal. TEST the system for normal operation.

Component Tests

Brake Booster

1. Check all hoses and connections. All unused vacuum connectors should be capped. Hoses and their connections

should be correctly secured and in good condition with no holes and no collapsed areas. Inspect the valve on the
brake booster for damage.

2. Check the hydraulic brake system for leaks or low fluid.

3. With the automatic transmission in PARK, stop the engine and apply the parking brake. Pump the brake pedal

several times to exhaust all vacuum in the system. W ith the engine switched off and all vacuum in the system
exhausted, apply the brake pedal and hold it down. Start the engine. If the vacuum system is operating, the
brake pedal will tend to move downward under constant foot pressure. If no motion is felt, the vacuum booster
system is not functioning.

4. Remove the vacuum hose from the brake booster. Manifold vacuum should be available at the brake booster end

of the hose with the engine at idle speed and the automatic transmission in PARK. Make sure that all unused
vacuum outlets are correctly capped, hose connectors are correctly secured and vacuum hoses are in good
condition. When it is established that manifold vacuum is available to the brake booster, connect the vacuum
hose to the brake booster and repeat Step 3. If no downward movement of the brake pedal is felt, install a new

brake booster.

5. Operate the engine for a minimum of 10 seconds at a fast idle. Stop the engine and allow the vehicle to stand

for 10 minutes. Then, apply the brake pedal with approximately 89 N (20lb) of force. The pedal feel (brake
application) should be the same as that noted with the engine running. If the brake pedal feels hard (no power
assist), install a new valve and then repeat the test. If the brake pedal still feels hard, install a new brake
booster. If the brake pedal movement feels spongy, bleed the brake system.
REFER to:

Brake System Bleeding

(206-00 Brake System - General Information, General Procedures) /

Brake System Pressure Bleeding

(206-00 Brake System - General Information, General Procedures).

Brake Master Cylinder

Usually, the first and strongest indicator of anything wrong in the brake system is a feeling through the brake pedal. In
diagnosing the condition of the brake master cylinder, check pedal feel as evidence of a brake concern. Check for brake
warning lamp illumination and the brake fluid level in the brake master cylinder reservoir.

Normal Conditions

The following conditions are considered normal and are not indications that the brake master cylinder is in need of repair.

Modern brake systems are designed to produce a pedal effort that is not as hard as in the past. Complaints of light
pedal efforts should be compared to the pedal efforts of another vehicle of the same model and year.
The fluid level will fall with brake pad wear.

Abnormal Conditions

Changes in the brake pedal feel or brake pedal travel are indicators that something could be wrong in the brake system.
The diagnostic procedure and techniques use brake pedal feel, warning indicator illumination and low brake fluid level as
indicators to diagnosing brake system concerns. The following conditions are considered abnormal and indicate that the
brake master cylinder is in need of repair:

• NOTE: Prior to carrying out any diagnosis, ensure the brake system warning indicator is functional.

Brake pedal goes down fast. This could be caused by an external or internal leak.
Brake pedal goes down slowly. This could be caused by an internal or external leak.
Brake pedal is low or feels spongy. This condition may be caused by no fluid in the brake master cylinder, reservoir
cap vent holes clogged or air in the hydraulic system.
Brake pedal effort is excessive. This may be caused by a bind or obstruction in the pedal/linkage, a faulty
non-return valve, booster or insufficient booster vacuum.
Rear brakes lock up during light pedal force. This may be caused by damaged brake pads, a partially applied parking
brake, a damaged ABS sensor or bearing failure.
Brake pedal effort erratic. This condition could be caused by the brake booster or incorrectly installed brake pads.
Brake warning indicator is on. This may be caused by low fluid level or float assembly damaged.

Non Pressure Leaks

Any reduced fluid volume in the brake master cylinder reservoir may be caused by two types of none pressure external
leaks.

Type 1: An external leak may occur at the brake master cylinder reservoir cap because of incorrect positioning of the
gasket and cap. Reposition cap and gasket.

Type 2: An external leak may occur at the brake master cylinder reservoir mounting seals. Repair such a leak by installing
new seals and make sure that the brake master cylinder reservoir retaining bolt is correctly installed.

Brake System - General Information - Brake System Bleeding

General Procedures

WARNING: If any components upstream of the Hydraulic Control Unit (HCU), including the HCU itself are replaced,

the brake system must be bled using Land Rover approved diagnostic equipment. This will ensure that all air is expelled
from the new component(s).

• NOTE: The following procedure covers bleeding the brake system if components down stream of the HCU have been
replaced. Where only the primary or secondary brake circuits have been disturbed in isolation, it should only be necessary
to bleed that circuit. Partial bleeding of the hydraulic system is only permissible if a brake tube or hose has been
disconnected with only minimal loss of fluid.

WARNING: Do not work on or under a vehicle supported only

by a jack. Always support the vehicle on safety stands.

Raise and support the vehicle.

Check that the brake fluid lines are secure and that there are no
signs of a brake fluid leak. If a brake fluid leak is detected,
investigate and rectify the cause of the leak before bleeding the
brakes.

Refer to:

Brake System

(206-00 Brake System - General Information,

Diagnosis and Testing).

Pump the brake pedal until the brake vacuum assistance is
exhausted.

WARNING: Do not allow dirt or foreign liquids to enter the

reservoir. Use only new brake fluid of the correct specification from
airtight containers. Do not mix brands of brake fluid as they may not
be compatible.

CAUTION: Brake fluid will damage paint finished surfaces. If

spilled, immediately remove the fluid and clean the area with water.

Remove the brake fluid reservoir cap.

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