VOLVO
ECM-0122 - Accelerator pedal (AP) position 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:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (10)
- Volvo C30 (2007–2013)2007Engine D4204T only
- Volvo C30 (2007–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo C70 (2006–2013)2008Engine D4204T only
- Volvo C70 (2006–2013)2009–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo S40 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo S40 (2004–2013)2007Engine D4204T only
- Volvo S40 (2004–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo V50 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo V50 (2004–2013)2007Engine D4204T only
- Volvo V50 (2004–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
What does this fault code mean?
The code is titled signal too low, but it concerns the pulse width modulated (PWM) signal from the accelerator pedal sensor to the engine control module. If that signal is faulty, the code is stored. Causes can be poor contact, breaks or shorts in the wiring, low battery voltage, or a damaged sensor.
Possible causes
- Looseness, contact resistance or oxidation in the connections
- Break in the signal wire
- Signal wire shorted to ground
- Break in the power supply or ground wire
- Low battery voltage
- Damaged accelerator pedal position sensor
What you can do
- 1With the ignition off, check the connector at the accelerator pedal sensor for contact resistance and oxidation
- 2Check the battery's charge and condition, since low voltage can cause the fault
- 3If you have a diagnostic tool, follow the pedal position in live data as you press and release the pedal, and check that the value tracks the movement
- 4Erase the fault code and test drive the car; if it returns, have a workshop check the pedal sensor and the wiring
Symptoms you may notice2
- Car feels weak or performs poorly
- Warning symbol and text message in the display
What the fault can affect1
- The analog accelerator pedal signal is used instead, if it is working correctly
General guidance for car owners. Diagnosis on the car can point to a different cause.