LDP Vacuum Solenoid Output Control

LDP (Leak Diagnosis Pump) VACUUM SOLENOID OUTPUT CONTROL
1998 MODEL YEAR M5.2.1 & ORVR COMPLIANT MS41.1 SYSTEMS


- The LDP solenoid is energized by the ECM by a switched frequency to ground. Engine manifold vacuum enters the upper chamber of the LDP to lift up the spring loaded diaphragm pulling ambient air through the filter and into the lower chamber of the LDP through the one way valve.







- The on/off frequency causes a repetitive pumping action on the diaphragm which provides the pressure for detecting leaks.
- The rate of the output control frequency is dependent on the feedback signal from the reed contact (see inputs) for determining system leaks.