VOLVO
ECM-0603 - Engine control module (ECM). Internal fault
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)
Show models by year and engine (14)
- Volvo C30 (2007–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo C30 (2007–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo C30 (2007–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
- Volvo C30 (2007–2013)2013Engine B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2005Engine B4164S3, B4184S11 only
- Volvo S40 (2004–2013)2006Engine B4164S3, B4184S11, B4184S8 only
- Volvo S40 (2004–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo S40 (2004–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2005Engine B4164S3, B4184S11 only
- Volvo V50 (2004–2013)2006Engine B4164S3, B4184S11, B4184S8 only
- Volvo V50 (2004–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo V50 (2004–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
What does this fault code mean?
The engine control module (ECM) runs internal checks on its memory and internal parameters. If it finds a fault in one of its own functions, the code is set, so the fault is in the control module itself. The fault may be permanent, or it may have occurred earlier and no longer be present. Intermittent faults can be caused by disturbances when the module starts up.
Possible causes
- Damaged engine control module (ECM)
- Temporary disturbance when the control module starts, for example from a weak battery
What you can do
- 1Read the code, clear it and road test the car; if the code does not return, the fault may have been temporary
- 2Check the battery condition and that the battery terminals are tight, since a disturbance at start-up can cause the fault
- 3Check that the engine control module's earth connections and supply connections are free from corrosion and secure
- 4If the fault returns after the road test, the engine control module is the likely cause and a workshop should replace it
Symptoms you may notice1
- No noticeable symptoms for the driver
General guidance for car owners. Diagnosis on the car can point to a different cause.