VOLVO
ECM-830B - 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 (9)
- Volvo C30 (2007–2013)2007Engine B5254T3 only
- Volvo C30 (2007–2013)2008–2013Engine B5254T7 only
- Volvo C70 (2006–2013)2006–2007Engine B5254T3 only
- Volvo C70 (2006–2013)2008–2013Engine B5254T7 only
- Volvo S40 (2004–2013)2005–2007Engine B5254T3 only
- Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
- Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
- Volvo V50 (2004–2013)2005–2007Engine B5254T3 only
- Volvo V50 (2004–2013)2008–2012Engine B5254T7 only
What does this fault code mean?
The engine control module and the generator's control module (ACM) communicate over the LIN network, and that communication has been disturbed. The fault may be caused by poor contact, a break or short in the LIN wiring, a fault in another module on the network, or a generator that is not intended for LIN communication having been fitted. The generator not charging warning lamp may light when the engine runs. The fault applies to the C30, C70 (06-), S40 (04-) and V50.
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
- Damaged generator control module (charge regulator)
- A generator with a control module not intended for LIN communication has been fitted
What you can do
- 1Read and note the code, clear it and switch the ignition on again to see whether it returns
- 2Has the generator or its control module been replaced recently? A generator not intended for LIN communication can cause the fault
- 3Check the connectors to the generator control module for contact resistance and oxidation
- 4Using a multimeter, check that the LIN wires are not broken or shorted to ground or supply voltage
- 5If the fault remains, have a workshop check the control modules on the LIN network and replace the generator control module if needed
Symptoms you may notice1
- The generator warning lamp (not charging) comes on while the engine runs
General guidance for car owners. Diagnosis on the car can point to a different cause.