VOLVO
ECM-801A - System relay. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
8 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), S60 (2001–2009), V50 (2004–2013), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (23)
- Volvo C30 (2007–2013)2007Engine D5244T8, D5244T9 only
- Volvo C30 (2007–2013)2008, 2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo C30 (2007–2013)2009Engine D4164T, D5244T13, D5244T8, D5244T9 only
- Volvo C70 (2006–2013)2007Engine D5244T8, D5244T9 only
- Volvo C70 (2006–2013)2008–2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo S40 (2004–2013)2006Engine D5244T8 only
- Volvo S40 (2004–2013)2007Engine D5244T8, D5244T9 only
- Volvo S40 (2004–2013)2008, 2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo S40 (2004–2013)2009Engine D4164T, D5244T13, D5244T8, D5244T9 only
- Volvo S60 (2001–2009)2006Engine D5244T4, D5244T5, D5244T6, D5244T7 only
- Volvo S60 (2001–2009)2007–2009Engine D5244T4, D5244T5, D5244T7 only
- Volvo V50 (2004–2013)2006Engine D5244T8 only
- Volvo V50 (2004–2013)2007Engine D5244T8, D5244T9 only
- Volvo V50 (2004–2013)2008, 2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo V50 (2004–2013)2009Engine D4164T, D5244T13, D5244T8, D5244T9 only
- Volvo V70 (2000–2008)2006Engine D5244T4, D5244T5, D5244T6, D5244T7 only
- Volvo V70 (2000–2008)2007Engine D5244T4, D5244T5, D5244T7 only
- Volvo V70 (2000–2008)2008Engine D5244T5, D5244T7 only
- Volvo V70 XC / XC70 (2001–2007)2006–2007Engine D5244T4 only
- Volvo XC90 (2003–)2006–2007Engine D5244T4 only
- Volvo XC90 (2003–)2008–2010Engine D5244T4, D5244T5 only
- Volvo XC90 (2003–)2011Engine D5244T18, D5244T4, D5244T5 only
- Volvo XC90 (2003–)2012All engines except: B5254T2, B6324S5
What does this fault code mean?
The relay holds on for a few seconds after the ignition is switched off, which gives the engine control module time to save and finish work in progress. If the relay cuts the voltage too early, the module registers a signal that is too low and sets the fault code.
Possible causes
- Poor contact, contact resistance or oxidation at the terminals
- Open circuit in the power supply to the system relay
- Open circuit or short to supply voltage in the signal wire to the relay coil
- Open circuit or short to ground in the wire to the relay contact
What you can do
- 1Read and note the code, clear it and road test to see whether it returns
- 2Check the connectors at the system relay and the engine control module for looseness, contact resistance and oxidation
- 3Check that the system relay receives its supply voltage
- 4Using a multimeter, check that the power wire between the engine control module and the system relay is not broken
- 5If no fault is found, have a workshop try a new system relay
Symptoms you may notice1
- Message in the information display
General guidance for car owners. Diagnosis on the car can point to a different cause.