This fix illustrates the power of the SureTrack community to quickly help a fellow tech solve a diagnosis problem. A SureTrack community member had a 2018 diesel, Volkswagen Transporter in the shop with the check engine light on and code P0401-00. They posed the question to the community and with the help of fellow community members, they were able to resolve the issue quickly.
The following Community Fix summarizes the interaction between members of the community that led to the solution.
Vehicle
2019 Volkswagen Transporter 2.0 Diesel
Title
Code P0401-00, Replaced Exhaust Gas Recirculation Valve
Complaint
The customer states the check engine light is on.
Cause
Connected a scan tool and found code P0401-00 – Exhaust Gas Recirculation (EGR) System: Insufficient Flow Detected. Used the scan tool to monitor live data and found the exhaust gas recirculation valve parameter was below specifications. Used the scan tool to repeatedly command the exhaust gas recirculation valve open and closed, monitored the valve position parameters on the scan tool and found the valve actual position parameter never matched the valve desired position parameter. Disconnected the exhaust gas recirculation valve connector, visually inspected the connector and terminals and found no obvious signs of damage. With the key on, engine off, used a multi-meter to check for the presence of voltage and ground at the exhaust gas recirculation valve and found both were present. Used the multi-meter to measure the resistance of the exhaust gas recirculation valve and found the measured resistance was within specifications. Removed the exhaust gas recirculation valve, performed a visual inspection of the exhaust gas recirculation valve and found it was clogged with carbon. The results of these tests verified the exhaust gas recirculation valve was faulty.
Correction
Replaced the exhaust gas recirculation valve, cleared codes, performed a road test and verified the vehicle operated properly. The check engine light did not illuminate and no fault codes returned.