VOLVO
ECM-U012D00 - Lost Communication With Generator Control Module. General Failure Information. No sub type information
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
9 modelsS60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
Show models by year and engine (18)
- Volvo S60 (2011–)2013Engine B5204T8, B5204T9, B5254T12, B5254T14 only
- Volvo S60 (2011–)2014–2015Engine B5204T8, B5204T9, B5254T12, B5254T14, D4204T5 only
- Volvo S80 (2007–)2013Engine B5254T12, B5254T14 only
- Volvo S80 (2007–)2014Engine B5254T12, B5254T14, D4204T5 only
- Volvo S80 (2007–)2015Engine D4204T5 only
- Volvo V40 (2013–)2013–2014Engine B5204T8, B5204T9, B5254T12, B5254T14 only
- Volvo V40 (2013–)2015Engine B5204T8, B5204T9, D4204T14 only
- Volvo V40 Cross Country (2013–)2013–2014Engine B5204T8, B5204T9, B5254T12, B5254T14 only
- Volvo V40 Cross Country (2013–)2015All engines except: B4164T, B4204T11, D4162T, D5204T6
- Volvo V60 (2011–)2013Engine B5204T8, B5204T9 only
- Volvo V60 (2011–)2014Engine B5204T8, B5204T9, B5254T12, D4204T5 only
- Volvo V60 (2011–)2015Engine B5204T9, B5254T12, D4204T5 only
- Volvo V60 Cross Country (2015–)2015
- Volvo V70 (2008–)2013Engine B5204T9 only
- Volvo V70 (2008–)2014–2015Engine B5204T9, D4204T5 only
- Volvo XC60 (2009–)2014Engine D4204T5 only
- Volvo XC60 (2009–)2015Engine B5204T9, B5254T12, B5254T14, D4204T5 only
- Volvo XC70 (2008–)2014–2015Engine D4204T5 only
What does this fault code mean?
The engine control module (ECM) controls the alternator charging voltage via LIN communication, on request from the central electronics control module (CEM) over CAN. The code is set when the engine control module detects that communication with the alternator control module (ACM) has stopped.
Possible causes
- Contact resistance and oxidation in the connections
- Short circuit between the LIN wires
- Open circuit in one of the LIN wires
- Internal fault in another control module on the same part of the LIN network
- Faulty alternator control module (ACM), including its charge regulator
- Alternator with a charge regulator that is not intended for LIN communication is fitted
What you can do
- 1Read the codes and first fix other LIN-related codes. Then clear this code
- 2Check that the fuses are intact and that the battery is well charged
- 3If the alternator has recently been replaced: check that it is intended for LIN communication
- 4Check the alternator and engine control module connections for oxidation. Look for chafed LIN wires and use a multimeter to check for breaks or shorts
- 5If you have a diagnostic tool: check the fault status indicators and freeze-frame values to see when the fault occurred
- 6If the fault returns: have a workshop with diagnostic equipment check the alternator control module and the alternator
Symptoms you may notice4
- The battery is dead or shows low voltage
- The engine is hard to start and the starter turns over slowly
- The engine lacks power, especially when the car is moving off
- The engine hesitates, surges or runs unevenly
What the fault can affect1
- The alternator control module charges at a fixed voltage
General guidance for car owners. Diagnosis on the car can point to a different cause.