Troubleshooting guide

COMPONENTS

FUNCTIONALITY OF THE EGR COMPONENTS

Variable Pressure Output Device (VPOD)

12 V/24V power supply system

DDEC I V ECM: PWM2 (Y1) EGR and PWM4 ( X2) VNT

Figure 2-4 EGR Val ve and VNT Control System

There are two Variable Pressure Output Devices (VPOD) that control the Variable Geometry

Turbo (VNT) and the EGR system. The location of the VPODs is application dependent. During

engine EGR operation, the VPOD provides modulated air pressure to the pneumatic actuators

which change the VNT vanes and EGR valve positions. The VPOD interface with other systems

maybeviewedinseeFigure2-4.

2-4 All information subject to change without notice. (Rev. April 2004)