VOLVO
CEM-1D04 - ECM, software. Faulty signal. Intermittent fault
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The CEM has registered faulty or altered engine control software (ECM). The fault is intermittent, so it may have occurred before without being active now. Correct software is downloaded by a workshop.
Possible causes
- An incorrect software checksum
What you can do
- 1With the ignition on, check that the code does not return after switching the ignition off and on again
- 2Has the car's engine software been modified? Discuss it with the owner before anything is changed, since the change may not be the cause of the repair
- 3Check that the battery terminals and cable connections are clean and tight, so the control modules get stable voltage
- 4Software is downloaded with diagnostic equipment and can only be done by a workshop
- 5After the work, clear the code and check that it does not return
Symptoms you may notice1
- No noticeable symptoms for the driver
General guidance for car owners. Diagnosis on the car can point to a different cause.