VOLVO
SUM-U201013 - Switch Illumination. General Electrical Failures. Bus off
System
Suspension Module (SUM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The SUM supplies and grounds the lighting in the Four-C switches. The fault code is set when there is a break in the lighting circuit, which means the lighting does not work.
Possible causes
- Break in the supply wire to the lighting
- Break in the ground wire to the lighting
- Damaged Four-C switch
What you can do
- 1Read the code, note it and clear it, then road test the car
- 2Check that the relevant fuses are intact; their locations are in the owner's manual
- 3Check that the connectors at the Four-C switches are firm and clean
- 4Inspect the lighting wires for breaks, chafing and pinch damage
- 5Use a multimeter to check that the supply and ground wires to the lighting have no break
- 6If the fault returns, have a workshop with diagnostic equipment check the switches and the wiring
Symptoms you may notice1
- The lighting in the Four-C switches does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.