Vacuum Pump, Brake System

��(Vacuum Pump, Brake System:

WIRING DIAGRAM

Vacuum Pump, Brake System: Component Location:

COMPONENT LOCATION VIEW

Vacuum Pump, Brake System: Component ID:

COMPONENT ID
1 Battery in the engine bay.
75 Distribution block, battery positive.
29 Brake lights switch beside the pedals.
342a Main fuse board in the engine bay.
458 Vacuum switch.
459 Vacuum pump.
460 Relay, vacuum pump, on the main relay board in the engine bay.

10-Pin Connector
H10-15 Behind the left-hand headlamp.

24-Pin Connector
H24-2 Behind the left-hand headlamp.

70-Pin Connector
H70-1 In the engine bay, behind the bulkhead partition.

Grounding Points
G2 Grounding point, behind the battery on the left-hand wheel housing.
G25 Grounding point, on the gearbox.

DESCRIPTION OF OPERATION
To boost the vacuum for the brake servo, a vacuum pump has been introduced on certain models.

When engine vacuum is insufficient, pressure switch 458 closes and grounds the coil in relay 460. The relay operates and motor 459 is supplied with current (+30 circuit) via fuse 13.

The vacuum pump runs until the right vacuum level is attained. The pressure switch then opens and the pump stops.

The relay coil is supplied with current (+54 circuit) via fuse 9.

FAULT DIAGNOSIS HINTS
1. Check that fuses 13 and 9 are intact and supplied with current.
2. Check that distribution terminal 231 is supplied with current.
3. Check the performance of the pressure switch.
4. Check the wiring harness, connectors and ground connections.