Here it is possible to perform a metering test to check that the volume of reducing agent that is metered out matches the volume calculated by the control unit.
The following text contains information about the test. We recommend that you read the whole text before you continue and start the test.
Note:
During the test reducing agent will come out from the pipe.
On certain vehicles the reducing agent tank must be removed to enable removal of the pipe. Then the reducing agent tank must be reinstalled before starting the test.
The catalyst in the muffler may be destroyed if reducing agent is sprayed into the catalytic converter when the vehicle is not running.
The test should be run three times, with three different metering volumes: low, medium, high.
Test conditions:
Ignition on.
Engine off.
Check that no error codes are stored in the engine control unit.
There must be reducing agent in the reducing agent tank and it may not be frozen.
The test requires a hose that is approx. 50 centimetres long and fits on the pipe.
A measuring beaker 200 millilitres.
Procedure:
The pipe for the reducing agent should be removed from the injection nozzle in the muffler before the test starts.
Use a box-end wrench to counterhold so that the injection nozzle does not rotate and break.
Install the hose on the pipe.
During the test reducing agent will come out from the pipe.
Collect the reducing agent in the measuring beaker.
Then compare the measured volume reducing agent with that stated in the test.
After the last test, wash clean with warm water to prevent spilled reducing agent from drying and forming crystals.