VOLVO
CEM-U300094 - Control Module. Component Failures. Unexpected operation
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsV40 (2013–), V40 Cross Country (2013–)
Show models by year and engine (2)
What does this fault code mean?
On the V40, the CEM has rebooted too often within a single operating cycle, which shows unexpected behaviour in the module. The code does not necessarily mean a hardware fault, since low battery voltage can also set it. The symptoms are similar to other CEM faults, such as poor performance, hesitation and gauge faults.
Possible causes
- An intermittent code is unlikely to point to a hardware fault in the module
- Low battery voltage can cause the code to be set
- The control module is damaged
What you can do
- 1Check that the battery is in good condition and the terminals are tight
- 2With a diagnostic tool, cycle the ignition once, read the codes again and check whether the code was active in the last cycle
- 3If the code was not active during the last operating cycle it is intermittent and needs no action
- 4If the code was active in this cycle, have a workshop with diagnostic equipment check the module and replace it if needed
Symptoms you may notice5
- The car performs poorly and lacks power, especially when pulling away
- The engine does not start, or cranks without starting
- The car hesitates, surges or feels jerky when driving
- Cruise control cannot be engaged
- Gauges show wrong readings or do not work
What the fault can affect1
- The functions of the central electronic module (CEM) are restricted
General guidance for car owners. Diagnosis on the car can point to a different cause.