Quote:
Originally Posted by Helmsman
My guy said the interface is control signal only with no feedback from the damper. If so in theory something could be broken in the signaling although the EDC module still believe things are fine. Hence testing that signal is the next step.
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It depends on how the EDC driver analog circuit is implemented. But yes there is no logical feedback from the damper to the EDC-K module. The only electrical part in the damper is the solenoid, there is no intelligence or internal sensor. But the EDC is driving a PWM current through each solenoid. That current has to loop back to the EDC module negative supply. Usually this kind of driver can detect an electrical fault (short overcurrent or open in the coil).
There is the possibility that BMW didn't exploit the PWM driver fault detection in its software implementation and that the drivers part of the EDC board has failed. If no current goes to the coil, that's proof. But EDC automatically turns off < 3 mph. Unless there is a test mode ?