VOLVO
ECM-C140 - Communication, central electronic module (CEM). Signal missing
System
Engine Control Module (ECM)
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:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (6)
- Volvo C30 (2007–2013)2007–2010Engine D4204T only
- Volvo C70 (2006–2013)2008–2010Engine D4204T only
- Volvo S40 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo S40 (2004–2013)2007–2010Engine D4204T only
- Volvo V50 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo V50 (2004–2013)2007–2010Engine D4204T only
What does this fault code mean?
The engine control module supervises the CAN link to the central electronic module (CEM). The fault code is set when the engine control module finds that the link to the CEM is not working. The cause can be the power supply, connections, wiring, or a CEM that is itself faulty.
Possible causes
- Fault-trace the CEM for CAN-related fault codes
- No power supply to the CEM
- Poor contact, contact resistance or oxidation in the connections
- Open circuit in the CAN network wiring to the CEM
- Internal fault in another control module on the same network section
- The CEM is not made for this car, for example a used unit with other software or hardware
What you can do
- 1Read out the fault codes in the CEM first, and fix any CAN-related codes there
- 2Check that the fuses for the CEM are intact and that the battery has enough voltage
- 3Check the connectors at the CEM and the engine control module for play and corrosion
- 4Look for breaks and chafing on the CAN wiring that runs to the CEM
- 5If the CEM has been replaced, check that it fits this exact car and has the right software
- 6Erase the fault code only after the faults are fixed, then road test the car to see whether it returns
Symptoms you may notice2
- A text message and warning symbol appear in the display
- Warning lamps and warning signals behave abnormally, for example the Check engine lamp
General guidance for car owners. Diagnosis on the car can point to a different cause.