Fuel injection for exhaust gas aftertreatment
Proceed as follows: Carry out the test "Checking fuel injection for exhaust gas aftertreatment" using SDP3. The test is stopped if the air pressure is not increasing even though the air control valve is open.If the test is stopped: Switch off the engine. Close and open the air control valve using SDP3. Check that the pressure in the parking brake circuit is sufficiently high. Listen for how the air control valve closes and opens. Check whether the air pressure changes when the air control valve closes and opens.If the air control valve opens: Check whether there are any leaks or blockages in the air pipes or in the pipe between the air control valve and the fuel injection nozzle. Check whether the pressure sensor is working by increasing or reducing the pressure in the pipe between the air control valve and the fuel injection nozzle.If the air control valve does not open: Check the connectors and electrical cables between the EEC control unit and the air control valve. If the connectors and electrical cables seem to be intact, renew the air control valve.When the fault has been rectified the fault code can be deactivated by carrying out "Checking fuel injection for exhaust gas aftertreatment" using SDP3.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
The air pressure in the valve block for exhaust gas aftertreatment is not increasing even though the air control valve is open.
Possible causes: The air control valve has not opened.Leakage in the pipe between the air control valve and the fuel injection nozzle.Leakage in fuel injection nozzle.Fuel injection nozzle cannot be closed.Fault in the sensor which measures the air and fuel pressure in the valve block.The vehicle's compressed air consumption is too high.The pressure in the pneumatic system of the vehicle is too low.Blockage in the air pipe to the air control valve.