VOLVO
ECM-951F - Accelerator pedal (AP) position sensor. Faulty signal
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsC70 Cabriolet (1998–2005), C70 Coupé (1998–2002), S60 (2001–2009), S70 (1997–2000), S80 (1999–2006), V70 (1997–2000), V70 (2000–2008)
Show models by year and engine (20)
- Volvo C70 Cabriolet (1998–2005)2000Engine B5244S only
- Volvo C70 Coupé (1998–2002)1999Engine B5254S DENSO only
- Volvo C70 Coupé (1998–2002)2000Engine B5244S only
- Volvo S60 (2001–2009)2001Engine B5244S, B5244S2 only
- Volvo S60 (2001–2009)2002Engine B5244S, B5244S2, B5244SG, B5244SG2 only
- Volvo S60 (2001–2009)2003–2005Engine B5244SG, B5244SG2 only
- Volvo S60 (2001–2009)2006–2008Engine B5244SG only
- Volvo S70 (1997–2000)1999Engine B5254S DENSO only
- Volvo S70 (1997–2000)2000Engine B5244S, B5244S2, B5244SG, B5244SG2 only
- Volvo S80 (1999–2006)1999–2000Engine B5244S, B5244S2 only
- Volvo S80 (1999–2006)2001Engine B5244S, B5244S2, B5244SG only
- Volvo S80 (1999–2006)2002Engine B5244S, B5244S2, B5244SG, B5244SG2 only
- Volvo S80 (1999–2006)2003–2005Engine B5244SG, B5244SG2 only
- Volvo S80 (1999–2006)2006Engine B5244SG only
- Volvo V70 (1997–2000)1999Engine B5254S DENSO only
- Volvo V70 (1997–2000)2000Engine B5244S, B5244S2, B5244SG, B5244SG2 only
- Volvo V70 (2000–2008)2001Engine B5244S, B5244S2, B5244SG only
- Volvo V70 (2000–2008)2002Engine B5244S, B5244S2, B5244SG, B5244SG2 only
- Volvo V70 (2000–2008)2003–2005Engine B5244SG, B5244SG2 only
- Volvo V70 (2000–2008)2006–2008Engine B5244SG only
What does this fault code mean?
The engine control module (ECM) compares the analogue signal from the accelerator pedal sensor with the PWM value reported by the throttle module (ETM) over the CAN network. If they differ by more than allowed for a longer time while the engine runs at higher speed, the code is stored. A larger difference is allowed while the pedal is moving.
Possible causes
- A connector on the digital PWM wire to the throttle module (ETM) has worked loose or has high contact resistance
- Fault on the PWM wire running from the engine control module (ECM) to the electronic throttle module (ETM)
- Interference on the CAN signal wiring
What you can do
- 1Read the fault code counter to see whether the fault is intermittent or permanent, and note the stored freeze-frame values for the operating conditions when it was first detected
- 2Check the connectors and wiring between the electronic throttle module and the engine control module for contact resistance and corrosion
- 3With a multimeter, check that the ground connections and voltage supplies to the engine control module and the electronic throttle module are intact
- 4If ECM-951F is the only stored code this is very unlikely. Look for a fault that keeps the signal within electrical limits yet still makes it wrong
- 5If you have a diagnostic tool: follow the accelerator pedal signals in live data while you press the pedal down and release it slowly, and see whether they track each other
- 6After repair: clear the codes, cycle the ignition off, on and off again, then test drive. A workshop should do a full reset of the throttle module if needed
Symptoms you may notice1
- Cruise control does not work at all
What the fault can affect3
- The throttle closes when braking, and the accelerator pedal position is ignored while the brake pedal is pressed
- Cruise control is switched off for the driving cycle in which the fault was detected
- The function is available again at the next start if the fault is no longer present
General guidance for car owners. Diagnosis on the car can point to a different cause.