4-Band VDSL CO/CPE MODEM USER’S MANUAL Ver. A.2
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Power and Cooling Problems
If the POWER indicator does not turn on when the power cord is plugged in, you may have a problem with the power outlet, power
cord, or internal power supply as explained in the previous section. However, if the unit power is off after running for a while, check
for loose power connections, power losses or surges at the power outlet, and verify that the fan on back of the unit is unobstructed
and running prior to shutdown. If you still cannot isolate the problem, then the internal power supply may be defective. In this case,
contact your dealer.
Installation
Verify that all system components have been properly installed. If one or more components appear to be malfunctioning (e.g. the
power cord or network cabling), test them in an alternate environment where you are sure that all the other components are
functioning properly.
Transmission Mode
The default method of selecting the transmission mode for RJ-45 ports is 10/100 Mbps Ethernet, for RJ-11 port are 5/15/25Mbps
VDSL. Therefore, if the Link signal is disrupted (e.g. by unplugging the network cable and plugging it back in again, or by resetting the
power), the port will try to reestablish communications with the attached device via auto-negotiation. If auto-negotiation fails, then
communications are set to half duplex by default. Based on this type of industry-standard connection policy, if you are using a
full-duplex device that does not support auto-negotiation, communications can be easily lost (i.e. reset to the wrong mode) whenever
the attached device is reset or experiences a power fluctuation. The best way to resolve this problem is to upgrade these devices to a
version that support Ethernet and VDSL.
