Unable to communicate with MD4 via ethernet

Currently trying to connect to an MD4-5 via ethernet (using D6). When I connect the ethernet cable to my computer directly from the MD4, it says it is offline and no master is selected. The MD4 also does not show up as a device on the same network. We are using a generic ethernet cable and wondering if this could be a wiring issue? MD4 powers up when the system is ON.