VOLVO
CEM-6C28 - Alarm LED. Faulty signal
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The CEM monitors the alarm status lamp on the dashboard. If the feed to the lamp is off, or the wire is short-circuited to voltage, the fault code is set. The fault shows as a faulty indication from the alarm lamp.
Possible causes
- Power feed to the alarm LED is off
- Power feed to the alarm LED is short-circuited to voltage supply
What you can do
- 1Switch the ignition on and check whether the alarm lamp lights constantly; if it does, the wire is probably short-circuited to voltage
- 2If the alarm lamp does not light, test it by activating it, with a diagnostic tool if you have one
- 3Check the connectors at the alarm lamp and at the control unit for loose connections and corrosion
- 4Use a multimeter to check that the power feed to the alarm lamp has no break and no contact with voltage
- 5If the wiring is intact and the fault remains, the alarm lamp should be replaced
Symptoms you may notice1
- Alarm lamp shows a faulty indication
General guidance for car owners. Diagnosis on the car can point to a different cause.