Abs Hydraulic Circuit And Solenoid Valve Function (Abs Without Traction Control)
| 1 - OUTLET VALVE |
| 2 - PUMP PISTON |
| 3 - PUMP/MOTOR (ON) |
| 4 - LOW PRESSURE ACCUMULATOR PRESSURE |
| 5 - LOW PRESSURE ACCUMULATOR |
| 6 - NORMALLY CLOSED VALVE (MODULATING) |
| 7 - TO WHEEL BRAKE |
| 8 - NORMALLY OPEN VALVE (MODULATING) |
| 9 - FROM MASTER CYLINDER |
| 10 - MASTER CYLINDER PRESSURE |
| 11 - CONTROLLED WHEEL PRESSURE |
| 12 - PUMP INTERSTAGE PRESSURE |
| 13 - NOISE DAMPER CHAMBER |
The hydraulic diagram shows the vehicle in the ABS braking mode. See Fig 1. The diagram shows one wheel is slipping because the driver is attempting to stop the vehicle at a faster rate than is allowed by the surface on which the tires are riding.
- The normally open and normally closed valves modulate (build/decay) the brake hydraulic pressure as required.
- The pump/motor is switched on so that the brake fluid from the low pressure accumulators is returned to the master cylinder circuits.
- The brake fluid is routed to either the master cylinder or the wheel brake depending on the position of the normally open valve.