VOLVO
CEM-DF13 - CAN-H, high speed network. Signal too high
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
10 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), S60 (2001–2009), S80 (1999–2006), V50 (2004–2013), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (10)
- Volvo C30 (2007–2013)2007–2013
- Volvo C30 Electric (2011–2013)2011–2013
- Volvo C70 (2006–2013)2006–2013
- Volvo S40 (2004–2013)2004–2012
- Volvo S60 (2001–2009)2005–2009
- Volvo S80 (1999–2006)2005–2006
- Volvo V50 (2004–2013)2004–2012
- Volvo V70 (2000–2008)2005–2008
- Volvo V70 XC / XC70 (2001–2007)2005–2007
- Volvo XC90 (2003–)2005–2015
What does this fault code mean?
The CEM registers CAN H in the high speed network as short-circuited to supply voltage. Throttle response and performance can then suffer, and the transmission control module (TCM) runs with limited function. The fault most often lies in the high speed network wiring.
Possible causes
- Short to supply on the high speed network
What you can do
- 1Check whether performance is reduced and whether any warning lamp is lit. This helps you judge how much of the car is affected
- 2Check the harness in the high speed network for chafing, pinch damage and moisture
- 3With a diagnostic tool, read the fault codes from all control modules and see which ones show communication faults
- 4Use a multimeter to check that the CAN H wire has no contact with supply voltage when it should not
- 5Check the connectors in the high speed network for loose connections and corrosion
- 6With the car in limp mode, do not drive far or in heavy traffic; have a workshop repair the fault
Symptoms you may notice5
- The malfunction indicator lamp is lit
- Performance is reduced
- The accelerator pedal responds poorly
- Radio interference
- A message appears in the text display
What the fault can affect1
- The transmission control module (TCM) runs with limited function
General guidance for car owners. Diagnosis on the car can point to a different cause.