BRAKES (Description): DESCRIPTION AND OPERATION (page 14 of 15)

BRAKES

70-18

DESCRIPTION AND OPERATION

The SLABS ECU continually calculates vehicle speed using the wheel speed inputs from all four ABS sensors. The 
calculated vehicle speed is then used as a reference against which individual wheel speeds are monitored for 
unacceptable acceleration or deceleration. The ABS sensor inputs are also used by the SLABS ECU to detect vehicle 
deceleration rate, vehicle cornering rate and rough terrain.

The engaged forward gear and (on manual gearbox models) the clutch status are computed from the engine data 
input, the engine speed input and vehicle speed. Reverse gear status is provided by an input from the reverse lamp 
switch (manual gearbox models) or the BCU (automatic gearbox models). On automatic models, the BCU also 
provides the neutral selected input.

In addition to controlling the brake related functions, the SLABS ECU:

l

Controls the operation of the self levelling suspension (SLS) system (where fitted). 
 

 + 

 REAR SUSPENSION, DESCRIPTION AND OPERATION, Description.

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On V8 models, outputs a rough road signal to the ECM when traversing rough terrain.

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Outputs a vehicle speed signal.

The vehicle speed signal is output to the following systems (where fitted):

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Active Cornering Enhancement. 
 

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 FRONT SUSPENSION, DESCRIPTION AND OPERATION, Description - ACE.

l

Air conditioning. 
 

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 AIR CONDITIONING, DESCRIPTION AND OPERATION, Description.

l

Cruise control. 
 

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 ENGINE MANAGEMENT SYSTEM - Td5, DESCRIPTION AND OPERATION, Description. 

 

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 ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine 

management.

l

Engine management. 
 

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 ENGINE MANAGEMENT SYSTEM - Td5, DESCRIPTION AND OPERATION, Description. 

 

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 ENGINE MANAGEMENT SYSTEM - V8, DESCRIPTION AND OPERATION, Description - engine 

management.

l

In-car entertainment. 
 

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 IN CAR ENTERTAINMENT, DESCRIPTION AND OPERATION, Description.

l

Instrument pack. 
 

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 INSTRUMENTS, DESCRIPTION AND OPERATION, Description.

5

Front right inlet solenoid valve

Output

6

Shuttle valve switches

Input

7

Rear left outlet solenoid valve

Output

8

Rear left inlet solenoid valve

Output

9

Centre differential lock switch

Input

10

Rear right outlet solenoid valve

Output

11

Rear right inlet solenoid valve

Output

12

Brake lamp relay

Output

15

Return pump relay

Output

C0655

7

Audible warning

Output

10

Engine speed

Input

Connector and pins not listed are either not used or used by the self levelling suspension system. 
 

 + 

 REAR SUSPENSION, DESCRIPTION AND OPERATION, Description.

Connector/Pin 

No.

Description

Input/Output