VOLVO
ICM-DC01 - Communication module. Faulty signal
System
Infotainment Control Module (ICM)
Volvo models this fault code applies to
Applies to the following models:
6 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013), XC90 (2003–)
What does this fault code mean?
The infotainment control module (ICM) can detect a break in the MOST network, the fibre-optic ring that links the infotainment modules. Although the code is labelled faulty signal, it describes that break in the network. While the break is present the infotainment functions shut down.
Possible causes
- Contamination or damage at the MOST cable connection
- Open circuit in the MOST cable
- Defective MOST transceiver in one of the modules on the network
- A module on the MOST network has no power supply
- Damaged module on the MOST network
What you can do
- 1Check that the fuses for the infotainment modules are intact. Their locations are given in the owner's manual or on the fuse box cover
- 2Check that every infotainment module receives power and has a good earth connection. One unpowered module breaks the whole network
- 3Look at the MOST connectors for dirt or damage and check they are firmly seated. Each connector carries two fibre-optic wires
- 4With a diagnostic tool, read the fault code after switching the ignition off and on, and see whether it returns
- 5If the fault remains, a workshop must run a ring break diagnostic with diagnostic equipment to locate the break
Symptoms you may notice4
- The audio unit does not work
- The display does not light
- Infotainment functions do not work
- Phone function absent or reduced
General guidance for car owners. Diagnosis on the car can point to a different cause.