GM Service Manual Online
For 1990-2009 cars only
Figure 1:

BPMV Hydraulic Flow


Object Number: 394564  Size: LF
(1)Master Cylinder
(2)Master Cylinder Reservoir
(3)Pump
(4)Brake Pressure Modulator Valve (BPMV)
(5)Damper
(6)Rear Isolation Valve
(7)Accumulator
(8)Rear Dump Valve
(9)Right Rear Brake
(10)Left Rear Brake
(11)Left Front Isolation Valve
(12)Left Front Dump Valve
(13)Left Front Brake
(14)Accumulator
(15)Right Front Brake
(16)Right Front Dump Valve
(17)Right Front Isolation Valve
(18)Damper
Figure 2:

Isolation Mode


Object Number: 394567  Size: LF
(1)Master Cylinder Reservoir
(2)Master Cylinder
(3)Ambient Pressure
(4)Master Cylinder Pressure
(5)Hold Pressure
(6)Accumulator Pressure
(7)Rear Isolation Valve
(8)Rear Dump Valve
(9)Rear Wheels
(10)Rear Accumulator
(11)Rear Pump
(12)To Front Channels
(13)Brake Pressure Modulator Valve (BPMV)
Figure 3:

Dump Mode


Object Number: 394568  Size: LF
(1)Master Cylinder Reservoir
(2)Master Cylinder
(3)Ambient Pressure
(4)Master Cylinder Pressure
(5)Hold Pressure
(6)Accumulator Pressure
(7)Rear Isolation Valve
(8)Rear Dump Valve
(9)Rear Wheels
(10)Rear Accumulator
(11)Rear Pump
(12)To Front Channels
(13)Brake Pressure Modulator Valve (BPMV)
Figure 4:

Reapply Mode


Object Number: 394569  Size: LF
(1)Master Cylinder Reservoir
(2)Master Cylinder
(3)Ambient Pressure
(4)Master Cylinder Pressure
(5)Hold Pressure
(6)Accumulator Pressure
(7)Rear Isolation Valve
(8)Rear Dump Valve
(9)Rear Wheels
(10)Rear Accumulator
(11)Rear Pump
(12)To Front Channels
(13)Brake Pressure Modulator Valve (BPMV)