VOLVO
ECM-P010F21 - Mass or Volume Air Flow Sensor A/B Correlation. General Signal Failures. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsS80 (2007–), V70 (2008–), XC60 (2009–), XC70 (2008–), XC90 (2003–)
Show models by year and engine (6)
- Volvo S80 (2007–)2007–2009Engine D5244T4, D5244T5 only
- Volvo V70 (2008–)2008–2009Engine D5244T4, D5244T5 only
- Volvo XC60 (2009–)2009All engines except: B6304T2
- Volvo XC70 (2008–)2008All engines except: B6324S
- Volvo XC70 (2008–)2009Engine D5244T4, D5244T5 only
- Volvo XC90 (2003–)2013–2014Engine D5244T18, D5244T5 only
What does this fault code mean?
The ECM monitors the mass air flow sensor signal and stores the code when it is too high or too low. Here the signal is too low. The fault concerns the comparison between the A-side and B-side sensors, and
Possible causes
- Signal wire shorted to ground
What you can do
- 1Read and note the code, clear it and road test to see whether it returns
- 2Check that the connectors at the mass air flow sensors are fully engaged and free from oxidation
- 3With a multimeter, check that the signal wire is not shorted to ground
- 4If you have diagnostic equipment, compare the A-side and B-side sensor values in live data at idle
- 5If the fault remains, have a workshop check the mass air flow sensor
Symptoms you may notice1
- The car has poor performance and lacks power
What the fault can affect2
- A calculated air mass value is used instead of the measured value
- Engine torque may be limited
General guidance for car owners. Diagnosis on the car can point to a different cause.