Known Issues - FPCM System

While the FPCM has the capability of detected failure modes, the faults are not always reported out as intended. Therefore, it is best not to rely on the DTC, or DTC Descriptions when deciding what portion of the system to diagnose. In most cases it is best to read and understand how the system operates, then diagnose the entire system to determine where the failure lies by performing the Complete Fuel Pump Control Module System Diagnostics  procedure when diagnosing this system. This applies to all vehicles equipped with an FPCM. The vehicles listed below will set faults incorrectly for the model years listed and should always be diagnosed using the system approach.

• DS - model years 2016-2019
• RU - model years 2017-2018
• JL - model year 2018
• JT - model year 2020

The exceptions to the information above are the Loss of Communication, Fuel Rail Pressure Sensor and Fuel Pump Relay Control circuit faults. These faults will typically set correctly since they are detected by the PCM directly, not the FPCM.