Caravan FWD L4-2.4L VIN X (1997)
Hydraulic Control Assembly - Antilock Brakes: Description and Operation
General Information
GENERAL INFORMATION
The Hydraulic Control Unit (HCU) used with the Teves Mark 20 ABS brake system is different from the HCU used on previous Chrysler products
with ABS. The HCU used on the Teves Mark 20 ABS system is called an integrated HCU. The HCU is called an integrated HCU because the
HCU and the Controller Antilock Brakes (CAB) are combined (integrated) into one unit. This differs from previous Chrysler products with ABS,
where the HCU and the CAB were separate components located in different areas of the vehicle. The Teves Mark 20 ABS system uses two
different HCU's depending on the type of ABS system the vehicle is equipped with. There is a unique HCU for a vehicle equipped with just ABS
and a unique HCU for a vehicle equipped with ABS and Traction Control.
Teves Mark 20 ICU
NOTE: The integrated HCU used on a vehicle that is equipped with only ABS and on a vehicle that is equipped with ABS and traction control
are different. The HCU for a vehicle that is equipped with ABS and traction control has a valve block housing that is approximately 1 inch longer
on the low pressure fluid accumulators side than a HCU for a vehicle that is equipped with only ABS.
Hydraulic Control Unit (Integrated) Mounting Location
LOCATION
The HCU is located on the driver's side of the vehicle, and is mounted to the front suspension cradle. The ABS only HCU contains the following
components for controlling the brake system hydraulic pressure during ABS braking: eight valve solenoids, (four inlet valves and four outlet
valves) fluid accumulators and a pump and an electric motor. The ABS With Traction Control HCU contains the following components for
controlling the brake system hydraulic pressure during ABS braking and traction control: four solenoid controlled inlet valves, four solenoid
controlled outlet valves, two hydraulic shuttle valves, two special valves, fluid accumulators a pump and an electric motor. Also attached to the
hydraulic control unit are the master cylinder primary and secondary brake tubes and the brake tubes going to each wheel of the vehicle..
CAUTION: The only parts of the hydraulic control unit HCU that can be replaced (serviced) is the CAB and HCU mounting bracket. The
remaining components of the HCU are not serviceable items. No attempt should ever be made to remove or service any other parts of the HCU.
This is due to the concern of contamination entering the HCU while performing a service procedure.
CAUTION: At no time when servicing the HCU should a 12 volt power source be applied to any electrical connector of the HCU.
