Description - ACE (FRONT SUSPENSION) (page 12 of 13)

FRONT SUSPENSION

60-20

DESCRIPTION AND OPERATION

Failure modes
Failures where the vehicle can still be driven safely are indicated by the ACE warning lamp illuminating continuously 
with an amber colour. The amber warning lamp will remain illuminated until the ignition is turned off. For all faults the 
warning lamp will only illuminate again if the fault is still present. Failures which require the driver to stop the vehicle 
immediately are indicated by the ACE warning lamp flashing with a red colour and an audible warning. All faults are 
recorded by the ACE ECU and can be retrieved with diagnostic equipment.

The following tables show the type of system failures and their effects on the system operation. Torsion bar 'floppy' 
means that fluid is allowed to circulate freely through the system. With no pressure in the actuators the torsion bar will 
have no effect on vehicle roll. 'Locked bars' means that all pump flow is directed through the valve block and returns 
to the reservoir. Both DCV's close and fluid is trapped in the actuators but can flow from one actuator to the other via 
the valve block. In this condition the torsion bar will perform similar to a conventional anti-roll bar, resisting roll but still 
allowing the axles to articulate.

Acceleration sensors

Pressure transducer

Road speed signal

21

Pressure transducer (earth)

Input

22

DCV 2 (earth)

Input

23

DCV 1 (earth)

Input

24

DCV 1 & 2 (supply)

Output

25

Pressure control valve (earth)

Input

26

Not used

-

27

Pressure control valve (supply)

Output

28

Main supply (+ V Batt)

Input

29 to 31

Not used

-

32

Main earth 2

-

33

Accelerometer - lower (signal)

Input

34

Accelerometer - upper (signal)

Input

35

Not used

-

36

Warning lamp

Output

Failure

Effect

Valve stuck closed

No ACE control

Short circuit - Ground

No ACE control

Short circuit - VBatt

No ACE control

Loose sensor

Erractic ACE activity when driving in straight line

Failure

Effect

Short circuit - VBatt

Large sensor dead band - possible random 
movements

Failure

Effect

Open circuit

No ACE control - 'Locked bars' condition

Short circuit - Ground

No ACE control - 'Locked bars' condition

Short circuit - VBatt

No ACE control - 'Locked bars' condition

Pin No.

Description

Input/Output