VOLVO
IHU-U1A2400 - MOST Ring Complete. No Communication. General Failure Information. No sub type information
System
Infotainment Head Unit (IHU)
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–)
What does this fault code mean?
The infotainment head unit (IHU) has detected that the fibre-optic data ring (MOST) is not closed. Audio, radio, navigation and phone communicate in a ring where each unit passes the signal on, so a break anywhere in the ring takes the whole system down.
Possible causes
- Dirt or damage in a fibre-optic connector
- Broken or sharply bent fibre-optic cable
- A unit in the ring has no power supply, for example due to a blown fuse
- Fault in one of the units in the ring
What you can do
- 1Check the fuses for all infotainment units
- 2Find out whether any audio or infotainment unit has recently been fitted, replaced or disconnected
- 3Check that fibre-optic connectors are fully engaged and the cables are not pinched or sharply bent
- 4With diagnostic equipment locate the unit that breaks the ring
Symptoms you may notice1
- Audio, radio, navigation and phone do not work
General guidance for car owners. Diagnosis on the car can point to a different cause.