Diagnostic Trouble Code (DTC) Information PHM-U210991

Condition 

Fig 1: Identifying Phone Module (PHM)

Courtesy of VOLVO CARS CORPORATION

The Phone module (PHM) checks the status of the internal reserve system that contains microphone, speaker, SIM card reader, battery and antenna.

The diagnostic trouble code is stored if the control module detects:

• Capacity too low on the spare battery.

Substitute Value 

• None.

Possible Source 

• Capacity of the internal reserve battery is too low.

Fault symptom[s] 

• Missing or reduced functionality for Volvo On Call
• Text window and warning symbol/Text message