VOLVO
ECM-135F - Mass air flow (MAF) sensor. 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 (20)
- Volvo C30 (2007–2013)2007Engine D5244T8, D5244T9 only
- Volvo C30 (2007–2013)2008–2010Engine 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 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 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 ECM continuously checks that the MAF sensor signal is plausible and follows the sensor's characteristic. The fault is set when the signal is faulty, so it can come from either a too high or a too low signal. A sticking swirl flap, moisture in the air filter or a leak after the turbo can be the cause.
Possible causes
- Leak in the hose or connection between the turbo and the intake pipe
- Damaged or stuck swirl flap
- Moisture in the air filter housing or the MAF sensor
- Clogged air filter
- Contact resistance or oxidation in the connections
- Damaged MAF sensor
What you can do
- 1Read the fault code, clear it and test drive to see whether it returns
- 2Check the hoses and connections between the turbo and the intake pipe for leaks and damage
- 3Check for moisture in the air filter housing and the MAF sensor, and replace a clogged air filter
- 4Check that the swirl flap moves freely and is not damaged
- 5Check the MAF sensor and boost pressure sensor connectors for contact resistance and oxidation; a damaged boost pressure sensor can also cause the fault
- 6If none of this gives a fault: have a workshop with diagnostic equipment check the MAF sensor and the EGR valve
Symptoms you may notice2
- Reduced performance and lack of power
- A text message appears in the display
What the fault can affect2
- Engine torque may be limited
- The engine control calculates the air mass instead of using the sensor reading
General guidance for car owners. Diagnosis on the car can point to a different cause.