Diagnostic Trouble Code (DTC) Information Bpm-B1D7984

Condition 

Bluetooth phone module (BPM) checks the signal from the microphone. The microphone belongs to the Integrated Audio Module (IAM) and communicates with the Bluetooth phone module (BPM) via the MOST-net.

The diagnostic trouble code (DTC) is stored if the control module detects that:

• The microphone has too low signal.

The control module's test for the diagnostic trouble code (DTC) starts in the event of:

• Ignition on and battery voltage between 9 and 16 V.

Fig 1: Identifying Bluetooth Phone Module (BPM)

Courtesy of VOLVO CARS CORPORATION

Substitute Value 

• None.

Possible Source 

• Internal malfunction in the microphone.
• Internal fault in integrated audio module (IAM).
• Internal fault in the Bluetooth phone module (BPM).
• The MOST network is not working.

Fault symptom[s] 

• Microphone does not work