Diagnostic Trouble Code (DTC) Information CEM-5F41

Condition 

Fig 1: Identifying Parking Heater

Courtesy of VOLVO CARS CORPORATION

The central electronic module (CEM) checks the communication with the combustion preheater module (CPM).

The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that the overheat protection thermostat has deployed.

The diagnostic trouble code (DTC) can be diagnosed when the heater is activated.

Substitute Value 

• None.

Possible Source 

• Air in the cooling system
• The cooling system is blocked
• Damaged overheat protection thermostat
• Damaged engine coolant temperature (ECT) sensor.
• Open circuit on fuel pump circuit.

Fault symptom[s] 

• Poor heating in the passenger compartment.