Variant 1: Exhaust gas circulation valve, position deviation
Applies to: EMS10
What does Scania EMS fault code 1181 mean?
The position sensor of the exhaust gas recirculation valve displays implausible open position values.
What causes Scania DTC 1181?
- Movement is limited near the open end position of the exhaust gas recirculation valve. - Leakage in the air supply to the pneumatic cylinder. - Faulty position sensor T124, actuator V107 or pneumatic cylinder.
What are the symptoms?
The check of exhaust gas recirculation becomes less reliable.
How to fix Scania EMS fault code 1181?
- Check that the pneumatic cylinder can move freely.
- Check that the exhaust gas recirculation valve can reach the fully open position.
- Check that position sensor T124 is correctly installed.
- Check the air supply from actuator V107:
- Loosen the air supply hose from the pneumatic cylinder and run an adaption sequence for exhaust gas recirculation.
- Check that air is flowing from the disconnected air hose during the adaption process.
- Check cable harness and harness-to-harness connector to the valve.
- Note: Delete stored adaption data if the exhaust gas recirculation valve, the exhaust gas recirculation position sensor or the pneumatic cylinder is renewed.
- The deletion prevents the fault code from recurring.
Variant 2
Applies to: EMS S7
Detection
The EGR valve position sensor T124 shows an implausible voltage value in the open position.
Possible cause
Possible causes are: - EGR valve position sensor T124 in incorrect position. - Fault on valve block V107. - Fault on the control cylinder.
System reaction
The engine will have trouble setting the right EGR content.
How to fix
- Check that the cylinder can be moved between the open and closed position, particularly to the open position.
- Check that the EGR valve position sensor, T124, is correctly assembled.
- Check air supply from the valve block V107.
- Check the circuit harness-to-harness connector and electrical cables.
- Note: Always carry out a basic setting and calibration of the EGR system using SDP3 after renewing the control cylinder, EGR valve or EGR valve position sensor T124.
Variant 3
Applies to: EMS S8
Detection
The EGR valve position sensor T124 shows an implausible voltage value in the open position.
Possible cause
- Fault in the air supply to valve block V107 or the valve block function. - The EGR valve cannot open because the compressed air pipe to the control cylinder is leaking. - The EGR valve position sensor T124 is defective or has become disconnected. - Fault in the EGR valve control cylinder. - Faulty EGR damper.
How to fix
- Check that the control cylinder can be moved between the open and closed position (particularly to the open position).
- Check that the EGR valve can move without binding.
- Check that the EGR damper is intact.
- If it is broken, it is important to check the silencer intake for loose parts which can damage the catalytic converters, if applicable.
- Check the air supply to the control cylinder and valve block V107.
- Check the EGR valve control cylinder and the harness-to-harness connectors and electrical cables in the circuit of EGR valve position sensor T124.
- Check if EGR valve position sensor T124 is defective or has become disconnected.
- After renewing the control cylinder, EGR valve or EGR valve position sensor T124, always run Functions > Calibration > Default setting and calibration of the EGR circuit.
This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.