VOLVO
ECM-0A09 - Transformer. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (6)
- Volvo C30 (2007–2013)2007–2010Engine D4204T only
- Volvo C70 (2006–2013)2008–2010Engine D4204T only
- Volvo S40 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo S40 (2004–2013)2007–2010Engine D4204T only
- Volvo V50 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo V50 (2004–2013)2007–2010Engine D4204T only
What does this fault code mean?
The engine control module (ECM) has logged an internal fault in the voltage converter that powers the piezo-electric injectors. The fault therefore lies either in the control module or in a relay that supplies it. It can cause starting problems and light the check engine lamp.
Possible causes
- Damaged system relay
- Damaged engine control module (ECM)
What you can do
- 1A workshop should check that the engine control module has the latest software and reload it if needed
- 2Check that the battery is in good condition and its terminals are tight, since voltage disturbances can affect the module
- 3If the fault remains after the software check, the engine control module is probably damaged and a workshop should replace it
- 4If the fault is permanent, a damaged system relay may also be the cause; have a workshop check it
Symptoms you may notice2
- Check engine lamp lit or behaving abnormally
- The engine does not start or turn over at start attempts
General guidance for car owners. Diagnosis on the car can point to a different cause.