Diagnostic trouble code (DTC) information CEM-1A5B

Condition 

Fig 1: Identifying Steering Wheel Module

Courtesy of VOLVO CARS OF NORTH AMERICA.

Diagnostic trouble codes (DTCs) are stored if the central electronic module (CEM) registers that communication with the steering wheel module (SWM) is not operating.

Substitute Value 

None.

Possible Source 

• No power supply to the steering wheel module (SWM)
• Open-circuit in the ground lead to the steering wheel module (SWM)
• Contact resistance in the terminals
• Open-circuit in the wiring for the CAN low speed network to the steering wheel module (SWM)
• The steering wheel module (SWM) is not intended for this car for example a used control module with different software/hardware).

HINT: If several diagnostic trouble codes (DTCs) are stored in the central electronic module (CEM) for communication faults with other control modules in the low speed network, this indicates a common fault in the Control area network, see appropriate wiring diagram. 

Fault symptom[s] 

• Cruise control does not function at all
• Windshield wipers only operate at lowest speed
• The turn signal lamps are not operating
• Buttons on the steering wheel are not working.