Mercedes-Benz Mercedes-Benz Vehicles (Multiple Models) Error Code P3005

Mercedes-Benz OBD-II Critical Emissions

Model: Mercedes-Benz Vehicles (Multiple Models) | Code: P3005

Applicable Systems
C-Class E-Class S-Class GLC GLE

Symptoms

DEF system performance fault; engine may derate or prevent restart after key cycle.

Possible Causes

  • DEF pump motor failure
  • DEF tank heater element open circuit
  • NOx sensor downstream signal implausible

Troubleshooting Steps

  1. Step 1: Check DEF quality and tank level
    DEF at proper concentration and level
  2. Step 2: Test DEF pump and heater circuit
    Components within specification
  3. Step 3: Replace DEF pump module if failed
    Pump replaced, DEF system primed

How to Reset

Clear codes and perform DEF system priming procedure.

Related Mercedes-Benz Fault Codes

Source: SAE J2012 Standard, OBD-II Service Manuals

Category: OBD-II