VOLVO
ECM-990F - Torque monitoring. Faulty signal
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), S60 (2001–2009), S80 (1999–2006), V50 (2004–2013), V70 (2000–2008)
Show models by year and engine (13)
- Volvo C30 (2007–2013)2007–2011Engine B5244S4 only
- Volvo C70 (2006–2013)2006All engines except: B5254T3
- Volvo C70 (2006–2013)2007–2010Engine B5244S4, B5244S5 only
- Volvo C70 (2006–2013)2011Engine B5244S4 only
- Volvo S40 (2004–2013)2004Engine B5244S4, B5244S5 only
- Volvo S40 (2004–2013)2005–2010Engine B5244S4, B5244S5, B5244S7 only
- Volvo S60 (2001–2009)2003–2006Engine B5244S, B5244S2, B5244S6 only
- Volvo S60 (2001–2009)2007–2009Engine B5244S, B5244S2 only
- Volvo S80 (1999–2006)2003–2006Engine B5244S, B5244S2 only
- Volvo V50 (2004–2013)2004Engine B5244S4, B5244S5 only
- Volvo V50 (2004–2013)2005–2010Engine B5244S4, B5244S5, B5244S7 only
- Volvo V70 (2000–2008)2003–2006Engine B5244S, B5244S2, B5244S6 only
- Volvo V70 (2000–2008)2007–2008Engine B5244S, B5244S2 only
What does this fault code mean?
The engine control module (ECM) measures engine torque by reading the acceleration of the flywheel and compares it with the torque requested by the accelerator pedal. Here the engine has produced more torque than requested, so the module has limited torque by cutting the fuel. The fault most likely comes from another problem in the system that produces too much torque.
Possible causes
- Air leak after the mass air flow (MAF) sensor
- Fault in the mass air flow (MAF) sensor
- Problem with the electronic throttle unit (ETM)
- Problem with the flywheel sensor
- Problem with variable valve timing (VVT) control
- Exhaust camshaft has jumped teeth
What you can do
- 1Read the fault codes in the engine control module and fault-trace the other codes first, since this code is most likely set together with codes for failing components
- 2Check that the mass air flow sensor hoses and connections are secure and airtight so that no false air enters after the sensor
- 3Check that the connectors to the throttle unit and the flywheel sensor are secure and free from oxidation
- 4With a diagnostic tool, compare the ranking values; a high Worst with a low Latest points to an intermittent fault or one that is not active
- 5Clear the fault code after the repair and road test the car to see whether it returns
Symptoms you may notice1
- Jerky driving
What the fault can affect3
- The cruise control is disengaged while the fault is active
- Engine speed and torque are limited by cutting the fuel supply
- How far they are limited depends on the accelerator pedal position
General guidance for car owners. Diagnosis on the car can point to a different cause.