Diagnostic Trouble Code (DTC) Information CEM-Dd1B

Condition 

Fig 1: Identifying Siren Control Module (SCM)

Courtesy of VOLVO CARS CORPORATION

When the alarm is activated, the central electronic module (CEM) checks communications with the siren control module (SCM) at regular intervals. The diagnostic trouble code (DTC) is stored if communication is disabled, despite several attempts.

The siren will also start to sound if communication stops.

Substitute Value 

• None.

Possible Source 

• Open-circuit in the signal cable to the siren control module (SCM)
• Internal fault in the siren control module (SCM).

Fault symptom[s] 

• False alarm