Diagnostic trouble code (DTC) information CEM-5F42

Condition 

Fig 1: Identifying Additional Heater And Parking Heater

Courtesy of VOLVO CARS OF NORTH AMERICA.

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

The diagnostic trouble code (DTC) is stored if the central electronic module (HEM) registers a short-circuit in the power supply from the combustion preheater module (CPM) to the fuel pump (FP), water pump and combustion fan.

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

Substitute Value 

• None.

Possible Source 

• Short-circuit to supply voltage in the power supply cable.

Fault symptom[s] 

• Poor heating in the passenger compartment.