VOLVO
ECM-13AD - Air temperature sensor. Signal too high
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The ECM watches the signal from the air temperature sensor, which sits inside the MAF sensor. The fault is set when the signal is too high or too low, so it works in both directions, even though the fault says too high.
Possible causes
- Signal wire shorted to voltage
- Damaged air temperature sensor
- Contact resistance, play or oxidation in the connections
- Open circuit in the signal wire
- Signal wire shorted to ground
What you can do
- 1Read the fault code, clear it and test drive to see whether it returns
- 2Check the MAF sensor connector for play, contact resistance and oxidation
- 3With a multimeter, check that the signal wire is not shorted to voltage or ground and has no break
- 4Check the wire for chafing and pinch damage, especially where it runs to the MAF sensor
- 5If the connector and wire are fine: have a workshop check the MAF sensor, since the air temperature sensor is built into it
Symptoms you may notice1
- No noticeable symptoms for the driver
What the fault can affect1
- A calculated temperature is used instead of the sensor reading
General guidance for car owners. Diagnosis on the car can point to a different cause.