The 1998 & later C-class have an interior CAN(computer) network. Each door has a control module! ON the rear the module is part of the window motor! Even the window switch is a computer!

THEY can be a problem to diagnose as one of the working modules can cause others on the network to go down! SCAN the system as upto 10 computers share that interior network!

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MERCEDES Benz Master Guild Technician (6 TIMES)
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