VOLVO
ECM-405C - Fuel level sensor. Faulty signal
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS40 (2004–2013), V50 (2004–2013)
Show models by year and engine (2)
What does this fault code mean?
The fuel level is used in the calculations when the leak diagnosis looks for leaks in the fuel tank system. The fault code is set when the engine control module has found an electrical problem with the level sensor and, in addition, a leak after the leak diagnosis, either a minor leak or a major leak. The fault most likely lies in the central electronic module (CEM), which should be troubleshot first.
Possible causes
- Electrical fault in the fuel level sensor
- Fault in the central electronic module (CEM), which should be troubleshot first
What you can do
- 1Have a workshop with diagnostic equipment read the fault codes in the CEM first and remedy them
- 2Do not clear this code until the fault code in the CEM has been remedied and cleared
- 3Check that the connector to the fuel level sensor is firmly seated and free from oxidation
- 4Look for chafed or pinched wiring to the fuel level sensor
- 5Have you got a diagnostic tool: read the fuel level in live data and check that the value is reasonable after refuelling
- 6Read the fault codes again after the repair and check that the code does not return
Symptoms you may notice1
- Fuel gauge shows a wrong value, too low
General guidance for car owners. Diagnosis on the car can point to a different cause.