Proceed as follows: Carry out the test "Checking fuel injection for exhaust gas aftertreatment" using SDP3. The test is stopped if the air and fuel pressure in the valve block for exhaust gas aftertreatment falls too quickly when the air control valve, fuel valve and fuel injection nozzle are closed.If the test is stopped: Switch off the engine 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 opens and closes. Check using SDP3 whether the air pressure in the valve block changes when the air control valve is opened and closed. Check whether there are any leaks in the pipes between the air control valve, the fuel valve and the fuel injection nozzle when the air control valve is closed.Remove the fuel injection nozzle and check whether there are any leaks. If the fuel injection nozzle is leaking, clean it as per the instructions in the Workshop Manual.Check the connectors and electrical cables between the EEC control unit and the fuel injection nozzle.When the fault has been rectified the fault code can be deactivated by carrying out the test "Checking fuel injection for exhaust gas aftertreatment".

Diagnostic depth