landrover Workshop Repair Guides

Land Rover Freelander System Manuals and Repair Guides

Operation|ABS|Page 302 > < Freelander 2001 TO 2004MY Onwards Workshop Manual - System Description and Operation - 5th Edition - NAS|ABS|Page 299
Page 213
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BRAKES

70-14

DESCRIPTION AND OPERATION

Operation

ABS
The purpose of ABS is to prevent vehicle wheels locking during brake application, thus maintaining vehicle steerability 
and stability. This allows the vehicle to be steered while the brakes are applied, even under emergency conditions, 
and to avoid obstacles where there is sufficient space to redirect the vehicle.

WARNING: ABS is an aid to retaining steering control and stability while braking:

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ABS cannot defy the natural laws of physics acting on the vehicle.

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ABS will not prevent accidents resulting from excessive cornering speeds, following another vehicle too 
closely, aquaplaning, etc.

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The additional control provided by ABS must never be exploited in a dangerous or reckless manner 
which could jeopardise the safety of driver or other road users.

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The fitting of ABS does not imply that the vehicle will always stop in a shorter distance.

NOTE: During normal braking the feel of the brake pedal on vehicles equipped with ABS will be the same as that on 
non ABS vehicles. During anti-lock braking operation the driver will experience feedback in the form of a pulsating 
brake pedal and solenoid/pump motor noise from the ABS modulator.

The anti-lock braking function is automatically enabled whenever the ABS modulator is in the normal braking mode.

While the anti-lock braking function is enabled, if the ABS ECU detects a wheel decelerating faster than the average, 
indicating it is about to lock, it operates the ABS modulator in the ABS braking mode for the affected wheel.

ABS ECU Connector Pin Details (Up To 2002 MY)

Pin No.

Description

Input/Output

1

System earth

2

Front LH ABS sensor

Input

3

Front LH ABS sensor

Input

4

Not used

5

Rear RH ABS sensor

Input

6

Rear RH ABS sensor

Input

7

Not used

8

ISO 9141 K line

Input/Output

9

Accelerometer supply

Output

10

Accelerometer earth

11

Brake switch (BTS contacts)

Input

12

Ignition power supply

Input

13 and 14

Not used

15

Battery power supply

Input

16

CAN bus 1 low (connection with instrument pack)

Input/Output

17

CAN bus 1 high (connection with instrument pack)

Input/Output

18

Brake switch (BLS contacts)

Input

19

Road speed signal

Output

20

Not used

21

Accelerometer signal

Input

22 to 27

Not used

28

Hill descent switch

Input

29

System earth

30

Front RH ABS sensor

Input

31

Front RH ABS sensor

Input

32

Not used

33

Rear LH ABS sensor

Input

34

Rear LH ABS sensor

Input

Operation|ABS|Page 302 > < Freelander 2001 TO 2004MY Onwards Workshop Manual - System Description and Operation - 5th Edition - NAS|ABS|Page 299