VOLVO
ECM-122C - Mass air flow (MAF) sensor. Flow too high
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (9)
- Volvo C30 (2007–2013)2007Engine B5254T3 only
- Volvo C30 (2007–2013)2008–2013Engine B5254T7 only
- Volvo C70 (2006–2013)2006–2007Engine B5254T3 only
- Volvo C70 (2006–2013)2008–2013Engine B5254T7 only
- Volvo S40 (2004–2013)2005–2007Engine B5254T3 only
- Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
- Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
- Volvo V50 (2004–2013)2005–2007Engine B5254T3 only
- Volvo V50 (2004–2013)2008–2012Engine B5254T7 only
What does this fault code mean?
The engine control module has found that the air mass measured by the mass air flow sensor is higher than the calculated value. The fault may lie in the wiring or in the sensor itself.
Possible causes
- Signal wire short-circuited to supply voltage
- Open circuit in the ground lead
- Damaged mass air flow sensor
What you can do
- 1Check the mass air flow sensor connector and wiring for chafing and loose contacts
- 2With your own diagnostic tool, read the air flow with the engine off and ignition on; the reading should be close to zero
- 3Use a multimeter to check that the signal wire has no contact with supply voltage and that the ground lead is not broken
- 4If the fault remains, have a workshop check the mass air flow sensor
Symptoms you may notice2
- The malfunction indicator lamp comes on
- The engine performs worse
What the fault can affect3
- Boost pressure is calculated rather than measured
- Rear oxygen sensor control is switched off
- Misfire detection is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.