If I understand what you are saying, the trailer brakes were being applied even when the tow vehicle brakes were not being applied. I suspect that the connection to the tow vehicle's brake lights is wrong. Some foreign cars have what us called an upside-down brake light connection, meaning that the connection point is hot until the brakes are applied, rather than cold until the brake lights are applied. I don't know if a Land Crusier is one of them - we need input from someone with a Land Cruiser, but it would account for the trailer brakes coming on when they shouldn't. Anyone?
At the bottom line, though, this can only be a wiring problem. The controller has a couple diagnostic lights - what do they say?
Not to be a wet blanket, but the Voyager is a time-delay controller, which was not a good choice. You might take a few minutes to read the tutorial on brake controllers in this forum's technical library, at
http://www.trailmanorowners.com/foru...ead.php?t=2830
Bill