VOLVO
DEM-U012100 - Lost Communication With Brake Control Module. General Failure Information. No sub type information
System
Differential Electronic Module (DEM)
Volvo models this fault code applies to
Applies to the following models:
8 modelsS60 (2011–), S80 (2007–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The four-wheel drive control module (DEM) continuously receives information from the brake control module (BCM), including the speed of each wheel, over CAN communication. If communication with the brake control module is lost, the code is set. The fault may lie in the brake control module, in the communication cable, or in the connectors between them.
Possible causes
- Open circuit in the communication cable
- Communication cable shorted to ground
- Communication cable shorted to voltage
- Contact resistance or oxidation in the connections
- Damaged brake control module (BCM)
What you can do
- 1Check that the fuses are intact; their locations are in the owner's manual or on the fuse box cover
- 2Test drive the vehicle to see if the fault returns, and note whether the brakes feel different
- 3If you have a diagnostic tool, read the brake control module fault codes first and remedy them before clearing this code
- 4Check the connectors on the communication cable for oxidation and loose fit, and follow the cable for chafing and damage
- 5The braking system is safety-critical: if the fault remains or the brakes feel different, have a workshop check the brake control module and the communication
Symptoms you may notice1
- Four-wheel drive does not work
What the fault can affect2
- Four-wheel drive is disengaged
- Four-wheel drive has reduced function
General guidance for car owners. Diagnosis on the car can point to a different cause.