Arduino long distance cable tester We have a 50 pair cable running about 1.5-2 KM with some services running on different pairs. One pair has recently become intermittent and is losing connection for 1-2 seconds at random. It might happen a few times an hour, so I jumped the service onto another pair. There is a modem connected to the pair for communication between two sites.

When resistance tested with a multi meter with a loop in one end it was reading 330 Ohms. When using an oscar meter it was reading -2.4db which is the same readings for other pairs.

I would like to use an Arduino to monitor the line resistance for a few days and see if there are any spikes or breaks in the line. I was going to use an analog input as a multimeter by using a known resistor and the looped pair as the other resistor. 

Does anybody think this will not work?

How else could I go about this?
Sure, no reason that wouldn't work. For best results you want a known resistor of about the same resistance as, or a little below, the one you are measuring. 

However, if what you are seeing is an actual open circuit then there's little benefit to measuring the resistance - you may as well just treat it as a switch or button, give it a large pullup, and use a digital input (or even an interrupt) to give a simple "OK / ERROR" signal.