Diagnostic Trouble Code (DTC) Information CEM-8FB2

Condition 

Fig 1: Identifying Rain Sensor Module (RSM)

Courtesy of VOLVO CARS CORPORATION

The central electronic module (CEM) communicates with the rain sensor module (RSM).

The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that the rain sensor module (RSM) has failed to adapt itself automatically to the windshield.

The diagnostic trouble code (DTC) can be diagnosed 2 seconds after the ignition is switched on.

Substitute Value 

• If the fault occurs more than 10 seconds after the rain sensor has been activated, the windshield wipers switch to high speed position.

Possible Source 

• Damaged rain sensor
• The rain sensor is not properly secured to the windshield
• Crack in the windshield by the rain sensor
• Stone chip on the windshield by the rain sensor.

Fault symptom[s] 

• No rain sensor function.