Applies to: EMS10
What does Scania EMS fault code 272 mean?
The engine management system (EMS) has detected a deviation for the value from the exhaust manifold exhaust gas pressure sensor (T271) when comparing with the value from other pressure sensors when the starter lock is turned to the position before the starter motor is activated.
What causes Scania DTC 272?
- Fault in the exhaust manifold exhaust gas pressure sensor (T271). - The harness-to-component connectors may be oxidised and make poor contact. - Moisture in the sensor may result in deviant values. - If the ambient temperature is below freezing, this may cause the sensor to freeze.
What are the symptoms?
Monitoring of misfires in cylinders 3, 4, and 5 is not working.
How to fix Scania EMS fault code 272?
- If the temperature is below freezing, make sure that the exhaust gas pressure sensor thaws before any other action is taken.
- Check that all sensors are working.
- Check the sensor's harness-to-component connector.
- Compare the value from the exhaust gas pressure sensor with the value from the atmospheric pressure sensor.
- A functioning sensor displays a value corresponding to atmospheric pressure, approx.
- 1,000 Pa (at sea level), when the engine is switched off.
- If the value from the exhaust gas pressure sensor deviates from this, the exhaust gas pressure sensor must be renewed.
- Perform a test again by turning the starter lock without starting the engine.
- The engine management system now carries out a check; the fault code should not be set or become passive.
This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.