VOLVO
ECM-0579 - Cruise control. Faulty signal
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)
What does this fault code mean?
The ECM keeps watch over the cruise control function and has logged a fault in it. This is a follow-on code: the steering wheel module (SWM) is not sending the cruise signal, so the fault lies in that module or the link to it. The check runs while driving. Fix the root fault first; the code can be cleared once that is done.
Possible causes
- The steering wheel module (SWM) sends no cruise control signal
- Fault in the steering wheel module (SWM)
- Open circuit or poor contact in the communication between the steering wheel module and the engine control module
What you can do
- 1Try the cruise control switches on the steering wheel: can the cruise be set and released as normal?
- 2Check the fuses for the steering wheel switches and the steering wheel module in the fuse boxes
- 3If work has recently been done at the steering wheel, such as replacing the clock spring, check that the connectors there are fully engaged and clean
- 4If you have a diagnostic tool, check the cruise control signal in live data while pressing and releasing the switches
- 5Have a workshop read out the steering wheel module (SWM) and check the communication; do not clear the code before the root fault is fixed
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.