DTC P1205 Dodge

Description

GENERAL OPERATION: When the Powertrain Control Module (PCM) receives a ‘Start’ or ‘Run’ signal, it energizes the Fuel Pump Relay which sends a continuous 12.0 volt supply to the Fuel Pump Control Module (FPCM). Depending on vehicle configuration, the Fuel Pump Relay can be either a removable component or be part of the Printed Circuit Board inside the Power Distribution Center (PDC) and not separately replaceable. The PCM sends commands to the FPCM through a Pulse Width Modulated (PWM) control signal. The FPCM in turn regulates the PWM voltage output to the Fuel Pump Assembly based on inputs from the Fuel Rail Pressure (FRP) Sensor and other engine demands. The PWM signal will vary from 10-100% to maintain the proper fuel pressure in the system. This is a Constant Pressure Fuel system which means any fuel pressure test performed on the Fuel Pump should show a continuous pressure (regardless of the changes in PWM).