A couple of months ago I bought a secondhand Rolec 7.2kw Type 1 tethered unit. It even had the original green RCBO, with no signs of burning contacts! It was cheap and looked simple enough to be durable. All was OK until about 2 weeks ago when I noticed it kept tripping said safety device. I bought a Garo equivalent to replace it after reading about the contacts overheating. This made no difference - the breaker trips as soon as my car takes current. I can only assume the little white module inside is faulty. Has anyone else had such an issue, and managed to return it to its former glory?