Check the circuit for the reductant heater for reductant hose 4 (H28).Further information about the electrical cables and pins on the control unit to which the component is connected is available in SDP3 under the tab Check for the relevant component. See also the Workshop manual, section 03-35 Electronic control system, E67.There is a general description of the different troubleshooting methods for electrical faults in the Workshop Manual, subgroup 16-70. Deactivate the fault code as follows: Switch the power off and on with the starter key.Carry out the test "Checking the reductant circuit" using SDP3.

Diagnostic depth