Proceed as follows: Carry out the test "Checking fuel injection for exhaust gas aftertreatment". The test is stopped if the fuel pressure in the valve block is too high or if the pressure falls too slowly when the fuel injection nozzle is opened.If the test is stopped: Remove the pipes between the air control valve and the fuel valve and fuel injection nozzle. Start the engine and check to see whether any of the valves is leaking.If any of the valves is leaking: Check the circuit connectors and electrical cables. If the connectors and electrical cables seem to be intact, renew the air control valve and fuel valve.Check the connectors and electrical cables between the EEC control unit and the fuel injection nozzle.Remove the fuel injection nozzle and clean it as instructed in the Workshop manual.Check that the fuel pressure sensor in the valve block indicates correct values, e.g. by increasing and reducing the pressure in the pipe between the air control valve and the fuel injection nozzle.Check that differential pressure sensor indicates correct values. Its value must be around zero when the engine is switched off.Check that the atmospheric pressure sensor indicates correct values. Compare the sensor values with the values from another atmospheric sensor.Check that the fuel injection nozzle opens. If it does not open, renew the injection nozzle.When the fault has been rectified the fault code can be deactivated by carrying out "Checking fuel injection for exhaust gas aftertreatment" using SDP3.

Diagnostic depth