Exhaust gas temperature sensor upstream of SCR catalytic converter
Proceed as follows: Check the circuit for the module for the exhaust gas temperature sensor.Check the connectors and electrical cables for CAN communication between the control unit EEC and the module for the exhaust gas temperature sensor.If the connectors and electrical cables seem to be intact, renew the module for the exhaust gas temperature sensor.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.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
The EEC control unit for exhaust gas aftertreatment has lost contact with the exhaust gas temperature sensor upstream of the SCR catalytic converter.
Possible causes: Electrical fault in the exhaust gas temperature sensor voltage supply.Fault in CAN communication between the EEC control unit and the exhaust gas temperature sensor.Internal electrical fault in the exhaust gas temperature sensor module.