GM Service Manual Online
For 1990-2009 cars only
BPMV: Brake Pressure Modulator Valve

CKT: Circuit

DLC: Data Link Connector

DMM: Digital Multimeter

DRP: Dynamic Rear Proportioning

DTC: Diagnostic Trouble Code

DUMP: Dump Valve

EBCM: Electronic Brake Control Module

EHCU: Electro-Hydraulic Control Unit

F4WD: Full-Time Four Wheel Drive

Infinite: Open Circuit/Immeasurably High Resistance

ISO: Isolation Valve

LPA: Low Pressure Accumulator

OL: Open Circuit/Immeasurably High Resistance

RWD: Rear Wheel Drive

S4WD: Selectable Four Wheel Drive

VSS: Vehicle Speed Sensor

WSS: Wheel Speed Sensor

The EHCU is the entire ABS assembly, including the BPMV and the EBCM. The BPMV is defined as the hydraulic control (lower) portion of the EHCU. It includes the internal control valves, the electric motor and the pumps. The EBCM is the electronic control (upper) portion of the EHCU. The EBCM mounts to the top of the BPMV. The EBCM is housed in aluminum with a black plastic top.