Fault code: 5729 SCANIA

Error identification:

The control unit detects a current that is lower than that which the control unit is trying to supply.

Cause:

Short circuit in the proportional valve circuit.

Notes:

The engine control unit switches off the EGR system and calibration of the mass flow sensor is switched off.

The fault affects the vehicle s emissions of nitrogen oxides (NOx) and the lamp which warns about a high level of contaminants comes on in the instrument cluster. A text message is also displayed in vehicles with NOx monitoring.

Vehicles with NOx monitoring

An active fault code cannot be cleared from the control unit. When the fault has been rectified, the control unit must verify that the fault has been rectified in order for the fault code to become inactive.

Action:

Check the circuit components, harness-to-harness connectors and electrical cables.

Proceed as follows to verify that the fault has been rectified:

Switch on the power with the starter key.

Activate the proportional valve for the EGR (part of valve block V107) by supplying 100% using SDP3.

If the fault is resolved, the fault code becomes inactive. Clear the fault code.

Switch the power off and on with the starter key three times in succession at 10 second intervals to turn off the warning lamp.