Abs Module And HCU

WARNING: This page is about a different car, the 2006 Land Rover Range Rover. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of JAGUAR CARS, INC.

Item Number	Description
1	ABS module and HCU
2	Brake pressure sensor
3	Bolt washer
4	Spacer
5	Mounting bush
6	Bracket mounting bolt
7	Mounting bracket

The anti-lock brake system (ABS) module is integrated with the hydraulic control unit (HCU) as one compact unit. This reduces the size and wiring required for DSC operation. Additionally the motor relay and valve relay have been replaced by solid state final stages in the anti-lock brake system (ABS) module. The anti-lock brake system (ABS) module and hydraulic control unit (HCU) are available as separate service components. The hydraulic control unit (HCU) uses:

Two pre-charge solenoid valves.
Two change over solenoid valves.
Four intake solenoid valves.
Four outlet solenoid valves.
One return pump.

Hydraulic Circuit

Courtesy of JAGUAR CARS, INC.

Item Number	Description
1	Fluid reservoir cap with fluid level sensor
2	Master cylinder
3	Pre-charge pump motor
4	Brake pressure sensor
5	Return pump motor
6	Pre-charge pump
7	Damper
8	Separation valve
9	Solenoid valve
10	One way check valve
11	Return pump
12	Check valve
13	Restrictor valve
14	Low pressure accumulator
15	Damper
16	Right Inlet valves
17	Left Inlet valves
18	Right outlet valves
19	Left outlet valves
20	Right rear brake
21	Left rear brake
22	Left front brake
23	Right front brake

The hydraulic control unit (HCU) controls the supply of hydraulic pressure to the brakes in response to inputs from the anti-lock brake system (ABS) module. The hydraulic control unit (HCU) is attached by three mounting bushes to a bracket on the left-hand (LH) wheel arch, and connected to the primary and secondary hydraulic circuits downstream of the master cylinder assembly. An electrical connector links the anti-lock brake system (ABS) module to the vehicle wiring. Internal passages in the hydraulic control unit (HCU), separated into primary and secondary circuits, connect to the various components that control the supply of hydraulic pressure to the brakes. Valves and check valves control the flow through the internal circuits. A damper chamber and restrictor are included in each circuit to refine system operation. Inlet and outlet solenoid valves control the flow to the individual brakes. An expansion chamber is connected to each circuit to absorb pressure. A return pump is connected to both circuits to provide a pressure source.

ABS Module Harness Connector C0506

Courtesy of JAGUAR CARS, INC.

ANTI-LOCK BRAKE SYSTEM (ABS) MODULE HARNESS CONNECTOR C0506 PIN DETAILS

Pin No.	Description	Input/Output
1	Ground	-
2	Battery power supply	Input
3	Pre-charge pump power supply	Output
4	Pre-charge pump ground	-
5	Ground	-
6	Battery power supply	Input
7	HDC active signal	Output
8	Lateral acceleration signal	Input
9	Yaw rate and lateral acceleration sensor test	Output
10	Yaw rate reference	Input
11	Diagnostic DS2 bus	Input/Output
12	Front left-hand (LH) wheel speed sensor signal	Input
13	Rear left-hand (LH) wheel speed sensor reference voltage	Output
14	Rear right-hand (RH) wheel speed sensor reference voltage	Output
15	Front right-hand (RH) wheel speed sensor reference voltage	Output
16	Front right-hand (RH) wheel speed sensor signal	Input
17	HDC switch	Input
18	Not used	-
19	Rear right-hand (RH) wheel speed	Output
20	Not used	-
21	Yaw rate and lateral acceleration sensor ground	-
22	lighting control module (LCM)	Output
23	Power supply from engine control module (ECM) relay	Input
24	controller area network (CAN) bus high	Input/Output
25	Brake pressure sensor ground	-
26	Brake pressure sensor signal	Input
27	DSC switch	Input
28	Front left-hand (LH) wheel speed sensor reference voltage	Output
29	Rear left-hand (LH) wheel speed sensor signal	Input
30	Not used	-
31	Rear right-hand (RH) wheel speed sensor signal	Input
32	Stoplamp switch	Input
33	Not used	-
34	Rear left-hand (LH) wheel speed	Output
35	Front left-hand (LH) wheel speed	Output
36	Brake fluid level switch	Input
37 and 38	Not used	-
39	Yaw rate and lateral acceleration sensor power supply	Output
40	controller area network (CAN) bus low	Input/Output
41	Yaw rate signal	Input
42	Brake pressure sensor reference voltage	Output