David Nelson

Emissions Technology Writer

David Nelson examines Volvo's aftertreatment systems - including DPF, DEF, and SCR - breaking down how they interact, how derates are triggered, and why troubleshooting in this area so often goes wrong. He explains the logic behind warning lights and the reasoning behind each targeted repair.

Articles

Volvo Penta Engine Fault Codes – Complete Reference Guide and Error Code Meanings

A practical guide to Volvo Penta engine fault codes, from flash codes to MID, PID, SPN, and FMI identifiers. Find common code meanings, possible causes, and diagnostic checks to help narrow down the problem before replacing parts.