Chrysler PT Cruiser Service & Repair Manual page 195

PT
HCU - HYDRAULIC CONTROL UNIT (Continued)
NORMAL BRAKING HYDRAULIC CIRCUIT,
SOLENOID VALVE, AND SHUTTLE VALVE
FUNCTION (ABS WITH TRACTION CONTROL)
The hydraulic diagram (Fig. 16) shows a vehicle
with traction control in the normal braking mode.
The diagram shows no wheel spin or slip occurring
relative to the speed of the vehicle. The driver is
applying the brake pedal which builds pressure in
the brake hydraulic system to engage the brakes and
stop the vehicle. The hydraulic shuttle valve closes
with every brake pedal application so pressure is not
created at the inlet to the pump/motor.
Fig. 16 ABS With Traction Control - Normal Braking Hydraulic Circuit
1 - OUTLET VALVE
2 - PUMP PISTON
3 - PUMP MOTOR (OFF)
4 - SUCTION VALVE
5 - LOW PRESSURE ACCUMULATOR
6 - NORMALLY CLOSED VALVE (OFF)
7 - TO RIGHT FRONT WHEEL
8 - NORMALLY OPEN VALVE (OFF)
9 - NORMALLY OPEN TC (ASR) VALVE (OFF)
10 - FROM MASTER CYLINDER
11 - HYDRAULIC SHUTTLE VALVE
12 - MASTER CYLINDER PRESSURE
13 - NOISE DAMPER CHAMBER
BRAKES - ABS 5 - 87