Range Rover Classic
70
BRAKES
2
DESCRIPTION AND OPERATION
ETC HYDRAULIC COMPONENTS
For full details of ABS components.
See Hydraulic
Components
1. ETC valve block
2. Power circuit solenoid valve - normally closed
3. Master cylinder isolating solenoid valve -
normally open
4. From accumulator
5. From master cylinder power valve
6. Power circuit to rear brakes
7. Power circuit to front brakes
8. PCRV valve
ETC OPERATION
When the wheelspeed sensors detect a rear wheel is
spinning at above vehicle speed, solenoid valve 3.
closes, isolating the master cylinder from the rear
brakes. Solenoid valve 2. is pulsed open, allowing
accumulator pressure to the rear brakes. The rear
brake ABS valves operate to apply or release the
brake at the spinning wheel as required.
FAULT DIAGNOSIS
Diagnosis is by TestBook or Wabco Diagnostic
Controller - STC 2 with software card, for both ETC
and non ETC vehicles. See also Range Rover
Electrical Trouble Shooting Manual.