Checking the power supply and ground for the phone module (PHM)

Check the fuse in the passenger compartment fusebox for the phone module (PHM).

Check the phone module (PHM) connector. Check for contact resistance and oxidation. Also check the connector. Check for damage.

Check the power supply cable between the fuse and the phone module (PHM). Check for an open-circuit.

Check the ground lead between the control module and the ground terminal. Check for an open-circuit. Also check the ground terminal. Check for contact resistance and oxidation.

Remedy as necessary.

Other information: 

• To access or replace the fuses, see Fusebox, passenger compartment, replacing
• To access or replace the keypad and phone module (PHM), see Phone module (PHM), replacing
• To connect the breakout box, see Connecting the breakout box. Carphone module 
• For information about signals and connectors, see Signal description. Phone module (PHM)
• For information about checking wiring and terminals see Checking wiring and terminals .

Fig 1: Identifying Breakout Box

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Ohmmeter

Courtesy of VOLVO CARS OF NORTH AMERICA.

Was a fault detected? 

• YES 

  Refer to Checking the function of the phone module (PHM) 

• NO 

  Refer to Signal missing