P20D7 OBD-II: Exhaust Aftertreatment Fuel Supply Control Circuit/Open

OBD II Fault Code

• OBD II P20D7

OBD-II Code Powertrain Control Module (PCM) failure is defined as a Exhaust Aftertreatment Fuel Supply Control Circuit/Open

Diesel Exhaust Fluid (DEF) is used to assist in converting leftover exhaust particles to harmless gases. In order to burn off those particles, the temperature of the exhaust system needs to increase. the injection of DEF Fluid into the exhaust stream brings Diesel Particulate Filter (DPF) up to temperature. The system is then able to convert harmful NOx to Nitrogen, Carbon Dioxide, and water. The DEF Pump creates hydraulic pressure to transfer the DEF from the tank to the injector. If DEF pump fails to operate properly, code P20D7 will set.

Powertrain Control Module (PCM) failure Symptoms

• DPF regeneration may not occur

Common Problems That Trigger the P20D7 Code

• DEF pump failure
• Powertrain Control Module (PCM) failure
• Wiring issue