3.2.127. SPN 3216, FMI 19, Upstream NOx sensor missingΒΆ

Description

The EEM4 monitoring system cannot detect the upstream NOx sensor.

Possible causes are:

  • The NOx sensor wiring is defective.
  • The NOx sensor is defective.

NOTE: The NOx sensor uses the vehicle CAN bus.

Reaction in EEM

The FC is stored and the warning lamp is activated. The CAN message indicates active fault.

NOTE: The present fault is classified as an emission related fault. Engine power will be reduced after a certain time which is defined by an authority.

Solution

First save the error log and then erase it. Restart the ECU after erasing the error log. If the fault occurs again during the next driving cycle, check the following paths:

  • Check the NOx sensor wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Check the operation with another NOx sensor to see if the sensor is defective.

See NOx sensor for reference.