Diagnostic trouble code (DTC) information CEM-4A34

Condition 

Fig 1: Identifying Fuel Pump

Courtesy of VOLVO CARS OF NORTH AMERICA.

The central electronic module (CEM) continuously checks the signal from the sensor on the ejector side which indicates the level in one of the fuel tanks.

The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers a short-circuit to ground in the sensor.

The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value 

• The fuel level is set to zero.

Possible Source 

• Short-circuit to ground in the sensor on the ejector side.

Fault symptom[s] 

• The trip computer displays an empty fuel tank too early.
• The fuel gauge indicates zero even though there is fuel in the tank.