Pressure Monitoring Module

The pressure monitoring module controls most electrical activity in the hydraulic unit, including the following functions.

• Pump Motor Control
  
  The pressure monitoring module receives an accumulator pressure input from two switches in the sensor block assembly. The module then commands the pump on and off to adjust accumulator pressure to its normal operating range. See Circuit Operation  for more detail.
• BRAKE Warning Lamp Control
  
  The pressure monitoring module also can turn the BRAKE warning lamp on in the event of low accumulator pressure or an internal pressure switch failure.
• System Fault Communication
  
  The module communicates low pressure conditions and other internal problems to the EBCM by means of the system fault line.
• Valve Relay Control
  
  The pressure monitoring module grounds the valve relay coil when commanded to do so by the EBCM. The EBCM commands the valve relay on by grounding the valve relay actuation line. The pressure monitoring module can disable the valve relay without being told to do so by the EBCM in the case of very low pressure and internal module failures.