On the RJ-11 connector end that plugs into the 'Wind" jack of the thermo/hygro sensor you could try seating the contacts. Lay the connector on something firm for support with the gold contacts facing up. Take a razor knife blade (exacto-knife) and use the blade's backside (dull) to firmly press the contacts down into each wire. This is where the connector gets crimped on initially and I've seen where they can become intermittent. You could also look inside the thermo/hygro sensor's 'Wind" jack to verify the connector wires are straight, not touching each other, etc.