Diesel Emissions Fluid (DEF) System: Description and Operation

Reducing Agent Metering System, Vehicles with SCR Catalytic Converter

Observe the following when working on the reducing agent metering system:

The reducing agent can cause skin irritation.

• Avoid contact with skin and eyes! Wear protective gloves!

• If reducing agent should get on your skin, wash it off immediately with soap and water.

• If reducing agent gets in your eye, rinse the eye for several minutes with water.

• Never inhale or swallow the reducing agent!

• Should you swallow any reducing agent, rinse your mouth, drink plenty of water and contact a doctor immediately.

Reducing Agent, Automatic Regenerating

• After turning off the ignition, any reducing agent is recirculated from the reducing agent injector (N474) metering line back into the active tank.

• Before working in this area, wait 10 minutes after switching off the ignition so that the recirculation can complete.

• Likewise, wait 10 minutes after switching off the ignition before disconnecting the battery so that the recirculation process can complete.

Danger due to reducing agent leaking out.

• To prevent large amounts of reducing agent when opening the metering line, wait for the recirculation process to complete.