Lowrance Ethernet problem

[WalleyeJig]

I have 2hds 8 s. I have changed the ethernet cable 2 times and still am getting an intermittent reading on the front graph. It's trying to take the sonar display from the back graph. It will show it then go blank. Than show it. Then go blank and so on. Is this a graph issue? Units are new.

[jhebert]

You have a problem with two devices communicating by a cable. You report that the front device does not receive communication via the cable from the rear device. Perform this test procedure:

--attempt to communicate by sending from the front device to the rear device. If this works, it verifies the cable is good in that direction;

--if the cable is good for communication when front sends to back, reverse the cable. This should cause the communication path to swap on the cable;

--now test again with sending from the front device to the rear device. If this works, you have verified the cable in both directions, and you can conclude the cable is good.

If reversing the cable produces a fault when the front device tries to send to the back device, the fault is in the cable. Replace the cable.

It is impossible to isolate the problem with sending from the back device to the front device to only one of the devices. You cannot tell if the problem is with the back device sending or the front device receiving. The only way to isolate this is to have a third device that is known to work in both directions. Substitute the third device that is known to be good in both directions for either the front or rear device in the test condition where rear is to send to front. Based on the outcome of this test you can tell if the problem is in the front device or the rear device.