VOLVO
ECM-4024 - Leak diagnostic unit, pump. Signal missing
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
8 modelsC70 Cabriolet (1998–2005), S40 (2004–2013), S60 (2001–2009), S80 (1999–2006), V50 (2004–2013), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (15)
- Volvo C70 Cabriolet (1998–2005)2003–2005
- Volvo S40 (2004–2013)2004Engine B5254T3 only
- Volvo S60 (2001–2009)2002Engine B5204T5, B5234T3, B5234T7, B5244T3 only
- Volvo S60 (2001–2009)2003Engine B5204T5, B5234T3, B5234T7, B5244T3, B5254T2 only
- Volvo S60 (2001–2009)2004Engine B5204T5, B5234T3, B5234T7, B5254T2, B5254T4 only
- Volvo S80 (1999–2006)2002Engine B5204T5, B5234T7, B5244T3, B6294S2, B6294T only
- Volvo S80 (1999–2006)2003Engine B5204T5, B5234T7, B5244T3, B5254T2, B6294S2, B6294T only
- Volvo S80 (1999–2006)2004Engine B5204T5, B5234T7, B5254T2, B6294S2, B6294T only
- Volvo V50 (2004–2013)2004Engine B5254T3 only
- Volvo V70 (2000–2008)2002Engine B5204T5, B5234T3, B5234T7, B5244T3 only
- Volvo V70 (2000–2008)2003Engine B5204T5, B5234T3, B5234T7, B5244T3, B5254T2 only
- Volvo V70 (2000–2008)2004Engine B5204T5, B5234T3, B5234T7, B5254T2, B5254T4 only
- Volvo V70 XC / XC70 (2001–2007)2002
- Volvo V70 XC / XC70 (2001–2007)2003–2004All engines except: D5244T
- Volvo XC90 (2003–)2003–2004All engines except: D5244T
What does this fault code mean?
The engine control module has noticed that the pump in the leak diagnostic unit gives a signal that is outside the expected range, or absent altogether. The leak diagnostic unit checks that the fuel system is sealed, and when the pump signal is wrong that diagnosis is switched off. The fault can be caused by the pump itself, the wiring or the connectors to the unit.
Possible causes
- Signal wire short-circuited to supply voltage
- Defective pump in the leak diagnostic unit
- Signal wire short-circuited to ground
- Contact resistance in the connections
- Open circuit in the signal or supply wire
What you can do
- 1Read and note the fault code, clear it and switch the ignition on again to see if it returns
- 2Check the connector to the leak diagnostic unit for contact resistance and oxidation
- 3Look for chafed or pinched wiring to the leak diagnostic unit, both the signal and the supply wire
- 4Use a multimeter to check that the supply and signal wires have no contact with ground or positive and are not open-circuited
- 5Have you got a diagnostic tool: read the pump signal in live data with the ignition on and check that it is present and steady
- 6Have a workshop check the leak diagnostic unit if the fault remains after checking the wiring
Symptoms you may notice1
- Malfunction indicator lamp (MIL) is on
What the fault can affect1
- The leak diagnostic is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.