VOLVO
CEM-1C01 - L signal. Signal too high. 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?
This code concerns the L signal from the generator, which is either too high, missing or shows a regulator fault. The fault is intermittent, so it has occurred before but may not be present right now. The generator may then stop charging and the battery discharges.
Possible causes
- The generator is not charging because it lacks an energy source
- A faulty central electronic module
- A diode fault in the generator
What you can do
- 1Switch the ignition on and check that the charging warning lamp lights. It should go out when the engine starts
- 2Check that the battery terminals and the ground connection are clean and tight
- 3Check that the generator drive belt is intact and tensioned correctly, and not slipping
- 4If you have a diagnostic tool, follow the battery voltage in live data with the engine running. The fault may be intermittent
- 5After the work, clear the code and check that the charging warning does not light again
Symptoms you may notice4
- The charging lamp lights while the engine is running
- The warning lamp does not light when the ignition is switched on
- The battery discharges
- The starter motor turns slowly
General guidance for car owners. Diagnosis on the car can point to a different cause.