Hydraulic Control Unit

ITEM	DESCRIPTION
1	Rear right brake connection
2	Rear left brake connection
3	Front right brake connection
4	Front left brake connection
5	Primary circuit connection
6	Secondary circuit connection

The Hydraulic Control Unit (HCU) is an integral part of the Anti-lock Brake System (ABS) control module, which is installed in the front corner of the engine compartment, on the driver side. The ABS is attached to a bracket installed between the front bumper mounting bracket and the suspension housing.

The HCU is a four channel unit that modulates the supply of hydraulic pressure to the brakes under the control of the ABS. The primary and secondary outlet ports of the master cylinder are connected to primary and secondary inlet ports of the HCU. The primary circuit in the HCU supplies hydraulic pressure to two separate outlet ports for the front brakes. The secondary circuit provides hydraulic pressure to two separate outlet ports for the rear brakes.

The HCU has three brake operating modes: Normal braking/(Electronic Brake Force Distribution) EBD; ABS braking; Active braking. Details of these operating modes are given in the Brakes Control service information.

For additional information, refer to: BRAKING CONTROL SYSTEM .