VOLVO
ECM-A10B - LIN communication. Alternator control module (ACM), faulty communication
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)2007–2011Engine 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)2005–2010Engine B5244S4, B5244S5, B5244S7 only
- Volvo V50 (2004–2013)2005–2010Engine B5244S4, B5244S5, B5244S7 only
What does this fault code mean?
The engine control module communicates with the alternator control module (ACM) over the LIN network, a simple serial communication link. The code is set when the engine control module detects interference in its communication with the alternator control module. The fault may therefore lie in the wiring between the modules or in either of them.
Possible causes
- Contact resistance and oxidation in the terminals
- Short circuit between the LIN wires
- Open circuit in one of the LIN wires
- Damaged alternator control module (ACM), which is also the charge regulator
- An alternator not designed for LIN communication is fitted
- Internal fault in another module on the same part of the LIN network
What you can do
- 1Check that the connector on the alternator control module is fully seated and free from oxidation
- 2With a multimeter, check that the signal wire between the engine control module and the alternator control module has no open circuit and no contact with ground or supply voltage
- 3Has the alternator been replaced recently? Check that it is intended for LIN communication, since a different alternator can cause this code
- 4If the wiring is intact, the alternator control module may be damaged; have a workshop replace it and then check that the fault is gone
Symptoms you may notice1
- The generator not charging warning lamp lights while the engine is running
General guidance for car owners. Diagnosis on the car can point to a different cause.