Fault-tracing information

Condition 

Fig 1: Identifying Active On Demand Coupling

Courtesy of VOLVO CARS OF NORTH AMERICA.

No diagnostic trouble codes (DTCs) stored in the control module for four wheel drive (Active on Demand Coupling).

Possible Source 

• Open-circuit, contact resistance, short-circuit to ground or short-circuit to supply voltage in the connectors for the brake control module or control module for four wheel drive (Active on Demand Coupling).

Fault symptom[s] 

• No four wheel drive.